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THli 



MAGAZINE OF SCIENCE 



A14D 



SCHOOL OF ARTS: 



;NDCD to illustrate the most useful, NOVBL and interesting PARl'S 

OF- 

NATURAL HISTORY AND EXPERIMENT.VI. PHILOSOPHY, 

AUTISTIC AL PUOCRSSKS, 

RNAMKNTAL MANUFACTURES, AND THE ARTS OF LIFE. 




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VOL. II 



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WITH nrwAUits nr ri?nt:K ii'yMtKt* and rirrv knchavings 



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PEE FACE. 



Tbs termination of a second volume caDs from us a few remarks, relative both to the 
past and the fatnre. The time daring which it has been in the course of publication, 
(from April, 1840, to April, 1841,) has been one rich in scientific discoveries. Were there 
DO ctkers than those relative to the different departments of Electricity, it would stamp 
a Tcnown npon the year that b past. But there are very numerous others, recorded in 
the fioUowing pu^, worthy of the utmost attention, and which most eventually lead to 
Rsalts of tihe ntraeet-valne to mankind. 

AB those discoveries we have taken especial «are to record, at as early a period 
«i it has been possible to obtain a full and correct account of them ; and if we have 
speared to neglect some subjects, which other periodicals have included in their current 
repoctSt it is becnnse they are not so valuable as, at first sight, they may appear ; (such, for 
example, as Autogenous Soldering,} or because the accounts known or given are too 
obscure to be intelligible, (such as Acrography ;) or it is possible, that with the most careful 
aeardi we may, by chance, have overiooked them. A few subjects have been delayed, only 
that we may introduce them with better effect in continued articles. Of this description 
ire the numerous Electro-Magnetic Engines, and which will meet with our immediate 
attention. 

With the advantage even of a proUfic scientific year, yet the whole learned worid does 
aat make sufficient discoveries to fill even a little work like this ; therefore we have had 
recourse to other matter, and explained such processes of art, and such phenomena of 
nature, as ore useful to be known, perfecting each part with that miscellaneous and 
cdentific information, which we have considered to be least known. Hence have arisen 
those extensive papers on Varnishing, the Analysis of Minerals, Botany, Galvanbm 
and Electricity, Idthography, and numerous others. 

The Queries which we have answered have been less than in the last volume, but the 
Correspondents we hyve attended to, have been incalculably more numerous ; and if we 



PREFACE. 

have not at all times attended to the wishes of our Friends, but tried their patiL^cc hy a 
delay in reply, it has arisen from causes over which we had no control. Some fow have 
complained to us of the omission of notices to Correspondents weekly. AVc regret 
that any person should be put to personal inconvenience, yet every one must admit that 
such an appropriation of space in all the numbers, by giving our work a temporary 
character, deducted much from its value as a volume ; and in answering Correspondents 
only on the wrappers of the monthly parts, we have been enabled to iill the space 
formerly occupied by notices with something of a more general interest, and at the same 
time have ensured a greater uniformity of appearance to the whole. 

In the third volume we shall go on in the same steady manner, and give our Trieadfl 
the earliest and the best information which we can procure on all matters relevant to the 
subject of science, particularly of the experimental parts of it ; and instead of flagging in 
our course, we trust to be enabled to impart to our work an increasing interest, by subjects 
not yet touched upon, as well as by the continuation of others, which we have hitherto 
been enabled only to commence. 

Our Friends will be glad to hear, that the remark we made in the first vokime b &o« 
still more i^licable ; that this work, which they have fostered with so much kindneUt 
continues to increase its sale — which, gratifying as it was a twelvemonth unce, is no* 
still more encouraging. To all our kind Friends, Contributors, and Headers, we return 
•or most sincere thanks. 

THE EDITOR. 



hb. Great Pretcttt Strttf, 
April U/, Itf41. 



THE 



AGAZINE OF SCIENCE, 



an& ^cI)ool of ^rt0* 



SATURDAY. APIK' '». ^W \[P«icb IJrf. 




ASTRONOMICAL ILLUSTRATIONS. 



iStcivioe of AttnmumT rrquires for iU ithistra- 
af^mtiu of A tnUlly JifFerrnt chAra>>tcr from 
Mher Bcienrc — no minute articles are 
Ired, nnthiug depends upun cither delicate 
m* nr quality of ingrcdientj, no jMui- 
cin occur : all is dark around — do noUe 
*y if tieariL all i% on a quiet scale, aud 
•UnUj u possible ; aU that is not to be seen 
wad dicTPgarded . that our attention mnjr not 
bat fixed and hTctted upon tbe one 
rbre our ey? ». 'Hie lecturer him«'lf is 
It our mindv msy be referred to tbe 
■fOl.. M. 



rniglity system of erealion. wbn^e illufitration we nrp 
witnessing. Another mark of di^tim-tifm between 
Astronomy and other sciences, is that tlicr nppeal 
to our senies, toonr ren^on and imn^aatinn — thus 
it hrcomes neceanry in lecturing on thin seienec to 
aim at immensity, and splendor of npparatoB, that 
the mind may a» faras is possible be made to |Ci'"''P 
some at least of thr infinilcly more stupendous 
apparatus of the universe. 

An account of ihe vertical tellnrian «« it i» cnlletl, 
or that nmrhine which repn-Fi'nt^ iht; mntion uf \hr> 
earth, will we arcture be iatcrcnung, and it U bvpcd 



MAGAZINE OF SCIENCE. 






illy u there is we birlieve no 
contuiu a plain dcscKption of 



>*ig. 1 reprewnU the mnrhine wlicn complete : it 
is sfeti to consist of the twelve signs of the xodiac, 
arranged in a circle, lii^ifvine the twelve montlit of 
the year. In the centre of thcue i? thft flun, and at 
four e(|ut>di6taiic polnii! a reprnentation uf the 
earth, as it appear* when entering into each of th« 
four scAsond : vhcn at B, opposite Ariei, U «iU 
enter the spring (luiirter, and the terminator will be 
seen passing through the pole — when opposite 
Cancer. D, it vrill be the summer solstice, the north 
pol« of the earth a* shown will ht* in darknri«9, the 
north pole consequently ohjccted to Iht sun's li^ht, 
making' <>ur »ummer. Three motithti af^erwanU it 
pasaM to Libra, or the nutuinnal <^uinox, uml when 
another quirter of the circle is couiplt;tc. it irill 
have pFtssed to Capricuni or miJ-wiiiter. When in 
action the whole will he indrtri(ne«s rxrrpt the twelve 
aigns of the xodiac, tiie eiirth and tho BUn. Th« 
coiutructiim of tlie mnchine i* a« follown : — The 
dottetl part of the first ri^nre showa a fi-ntuc work 
of 8tn)n^ timber, the whole heini; bs Urge ms the 
room in which it is to be exhibited will allow to be 
used wit I t:: for theatrical exhibition 50 

or 40 i\- ■ iHiinl, for private use it must 

be at ii'.t.-. i _.j i>iri. 

The si^nj shonid be at least 3 feet diameter, and 
placed cUy-i-- "i- nr .-irK .-l.^ip. together in the ctrrle ; 



irih 18 inche^^f either 

:II hv icreutly diminished, 

Mce di.<iKatiflf4Ctf0nt 

than diminuHTV 

-Ircuiiifltancee will 

it iii fnr bettor to 

t<i><iii'->i u) a magic lanthonu 

idl na not to raise a feeling of 



the Bun .' 

be less til. 

for uoLliiui; iii tiintL- i 

and it mnv h** Mt 

ast 

no. 

tni'i "• > ' 

thnn iUff 

awe und ^ - ■- . 

Thr next cut -hows the same marhine viewed 
^dewiiy^- The rtxit and stning apright support 
A A show the dotted part »mu in the former fiKUit. 
with the exoeptkan of the frame work, which 
supportc tho sijpis of the iodine. B B are two 
opposite si^ns, oilhorof which ^bows the structure 
of the whcif*. They are mfidc lik. ' ■ . • round 
piece of woud f»rm» the tijuk, > Ix-in^ 

I'Ut in the lower part of it, to ad^... .... . . i.cd the 

candle llame. Tlie sidea may be of brown paper, 
with three or four wooden nbs, to suMnin the 
brown paper uf iu proper shape, and also to hold 
a tight hoop, which Koishe^ it towards the front. 
Tlie picture is n comrnon trnnsparcDcy, fastcneij on 
a hoop, which will fit upou the front of the paper 
drum. it is li«;htcd by a solitary wax, candle, 
which ii fuminbcd with a tin chi:iiney passing 
through the back to carry olf the smoke. 
C is the earth, afterwards to be de.v:rihed. 
D is the sun, formed of two drums, the outer 
one is farmed exactly like those of the sij^s, 
except as tu cnndle and chimney : it ii fa^^tened to 
the part K, tht<t is representeil at F F. Within is 
another drum <i, havinj^ within it u cnndleitick, 
snpported by its centre, holding' a candle below, 
and a flit pirec of tin over the cuiidle to prevent 
its burning the top. The candh-^tirk is miidc 
moveable, in order that the candle should be per- 
pendtculjr, notwithstiinding the rapid rcrolubon of 
Uie other part. 

The ^nt of the «un b made of varnished silk ; 
w irtaler brilliancy, the two druma have rays 



painted on them in nratrary directions. »* i«pff»< 
eeoted when treatinf of Chinese Flr«woriD ia tlif 

former volume. 




The requisite raotions arc, that the sun shnnld 
hate a dazzlinfc sciotillntini; nppejironoe |:iven to it. 
and that the earth should turn on its ajris, at tho 
same time that it revolves in its orbit around the 
sun. also that at two parts of its course Its axia 
should be pirallel to the sun, at the iutermcdiala 
poinU it »ho<ild be inclined at the proper ani^le 
234 • All this is done by an ertremely simfite 
■rran^ment of whecUwork ; we hnre reprvseotod 
it by wheels and cords, as working without noiaft; 
it may be moved, however, by cogged wheels, with 
the same effect. Mr. WoUis's machinery is « 
mixture of both, chiefly the Utter. K ia a wheul 
worked by a handle, it passes through the upright 
support A, and has upon the other side of A « 
small pulley L. The wheel K tarns a smitU poUef 
I. which paaiing through to the drnm O, ke<Ti» it 
in rspid motion, the candle within it standing still- 
The puller I. tarns a large wheel at the back of the 
bur of wood E. This lar^e wheel being fastened to 
E tarns that round also, and consequently moves 
the earth in its orbit, and equally keeps in motion 
the second transparency of the stin. The ejtrth U 
tamed on its axis by means of a second : 
there is on the wheel at the back of E, ch 
cord over a pulley aC N. O b merely a i...*i..r.. 
poise weight for the earth A the opposite end of the 



ThA rcUtive rapidity of the ruioiu 
of 00Qr»e depends apoa the reltUve pro- 
y4ft5on of the ranous wbrcb. 

The atmctare of this imitative earth U better 
Kco in the accooipaityiiig rigurc. 




_A, the part wen in front, u formed of a irire 
work, (the wires fonning the lines across it,) 
with MctioQs of muslin, punted ao as to 
nt a north polnr projiM-rinn of the earth. E 
dram made 3A in the fortntrr iastnnctfa. B ia 
- ' ' "1. a* in tlic sun before men- 
) ^^hiah tumii u\\ iC-« a\ia. D 
fBt<i:i : (ipurt. If it be requisite that 

lM|ue to itB orbit of rcvolotion, 
y properly lo show the WJtsons, 
**tuc <iJuUi'.iuicc and adjustment ia ut-cc^sary 
wtj mtli(-j(Cf>d m the df-ai^ription of the horizuntdl 
tiutii fonner rolume. 

now described is e<|ually applicable 
to iiin« inc ution nf the tides, the lunar malions, 
Mtiptea, and the p^icrsl nfrMii^rincnt of the solar 
Tbetc applications ne purpose lu recur to 



CITRIC ACID. 

Ttt"; ■-■-' ""ff. in many tejeUihlfji, cither free, or 

&> < lime: it 'w especially nbundiint in 

\< im which it vai first obtained in a 

- I by Scheele : it ii eontained iu 

irpbcrriea, and other fruits, and U 

'. with niidic acid. 

abtnined from lemon or lime-juice 

T. Boil the expressed juice for n few 

and. when cold, strain it through fine 

' ' .lert!(l ehalk an lony Z6 it pro- 

lirnt thf mixture, and strain as 

:( citrate uf lime remains upon 

Uicb, havin|j[ been wiuhed with cold 

put into a mixture of sulphuric acid 

•*rta uf water: the proportion uf acid may 

r-qttnl to that of the chalk employed. In 

1--, tJiC citrate of lime will have 

m, and sulpbiitt: of lime is 

iratrd by filttBtion. The fil- 

!'j1 evaporalioo, furnishes crys- 

lOQ of this acid is carried on by a 

ih 'ti>un on eatensiTc aca]e ; in dif. 

. . it i* employed by the cjilico- 

< JomeMic consumption. Many 

'Ujch biivc not here been alluded to, 

' trn«ure roniplcle tiacceaa in the ope- 

tiM»« nira boni folly dticribed by Mr. 



Pttriet. In the third volame of his CMtmiciU Smafft, 
The avcraiie proportion of citric acid afforded by a 
gallon of good lemon<juice, is nhout eight ounces. 
Dr. Henry states that he haa obtedned as much aa 
twelve ounces. 

Citric acid forms bcaotiful crystaln. of which the 
primnry form is a right rhombic pri<m. They have a 
a very !iour tnste, and are soluble in somewhat lesa 
than their own weight of water at 60". and in half 
their weight at 212 . They also dissolve in alcohoL 

M. niioy, of Dijon, recommends gnosebcrrtes as 
ft source of citric acid: they nre bniiced, and the 
expressed juice is fermented, and thru diAtilled lo 
obtain the alcohol : the rosidae is saturated by 
chalk, and the wuhed citrate of liuir dty-omposed 
by Eotphuric acid : from lUI) parts of gooseberries 
be obtained 10 of alcohol and 1 of acid. 

Citric acid is sometimes fradulently mixed with 
the tailaric : the adulteration may be discovered by 
jgradually adding to the acid dissolved in wntej-. a 
solution uf carbonate of poiassa. which will occa- 
sion the precipitation of bitartralc of poto&sa, if 
tATtanc acid be present. 

The crystals of citric acid include a certain pro- 
portioff of water, part of whiih may be expelled by 
heat I LU its ajthydrvut state, as it BKiata combined 
with certain bases. 

The crystals of citric acid, deposited from its 
saturated solution at 212'^ contain 1 atom of water. 

These crystals fuse at a little above 212"^, into a 
limpid litjuid, wilbout lo^s of weight, and concrete 
on cooling into a solid transparent moss. The crys- 
tals whieb oTd obtained by the fepoittoneouii rvapr*- 
ration, nt common temprraturea, of a solution of 
citric acid, differ in cumpusition frum the former 
and contain 3 atom^^ of anhydrous acid and 4 of 
water. These crystals are permanent at common 
teiDperaturetf, but when dried at 212'' tliey effloresce 
and lo»e exactly h.nlf their weight of water. When 
any attempt is made to drive off more wotcr by the 
ap]>tication of higher temperature, the acid is ilfeclf 
decomposed. 



ATMOSPHERIC ELECTRIC1T\'. 

(RegmnedfrompagtZ^Xt VoL /., and conettdtdj 

Anrifra BorealiM. — After the identity of light- 
ning and the electric fluid was established, the 
expUoation of llie Aurora Borealia w»s cosy. Mr. 
Dalton gives a Mpiritetl description of onr, which 
appeared on the 13tb of October, i;92. He says, 
" There first appeared a dull red light. sutficientJy 
stron),' to read by; all on a sudden the whole 
hemisphere was covered with streams of tight, ond 
exhibited «uch an appearance aa surpawee all dv- 
Hcription. Tlie inteusity of the light, the prodigious 
number and volatibihty of tlie beams, the grand io- 
trrmiature of all the priamotic colors in their utmost 
splendor, variegating the glowing cauupy with the 
most luxuriuQt and enchanting scenery, afforded on 
awful, but at the saint' ttaic the most pleasing and 
sublime spectacle in nature. The point to which all 
these beams and flashes tended, was in the magnetic 
meridian, and oa near as could be determined Xh" op 
20"" south of the zenith. The Aurora continncd, 
though diminishing in splendor for several hours." 
When the Northern lighta appear in this country, 
they occur chiefly in the Spring or Aotnmn, and 
u&uolly after a period of dry weather. They ore 



MAGAZINE OF SCIENCE. 



n more rarely in coanLries nctr the equator, but 
visible almost coofUDtly during tiic Iuiije: n'inteni 
jn tJic poUr regions, and with a lustre of which wt 
form but a faint conception. 

In the Shetlanil Islands thejr nre called " titerty 
^aneert," and are the regulnr alieiuUnti of clear 
weather, g»iu£ a diversity and dieerfulnefig to the 
long winter nighu. In 'Hudt*on*« bay the reftil- 
genctt of the Auroro in stated to be frequently cijuul 
to tbot of the fall moon. In the Ntirthem latitudes 
of Norway and Sweden, their brilliancy is ko re- 
markable and coDHtant, as to enliven the path of the 
trAvrUer during cbo whole night. In the N.E. part 
of Siberia, they are also dawribed as moving with 
ini:redlb)e velocity, and clothing the Aky with a mottt 
briUiotitlj- luminous appearance, resembling a vast 
expanded tent, covered with gold, lapphirea, and 
rubies. 

Tbe reasons why this phenomenon has been at- 
tributed to Electricity, are, 1st. That whenever U 
appear*, the atmosphere in found replete with the 
electric fluid. 2nd. It ctjunUy, with electricity, 
influciicr^ the magnetic needle. It puts on appear- 
ances dilTereDt from lightning becnnsc it occar» at a 
codudcrable altitude above the earth, wbfere of 
course tlie air is much rarefied. If this be the ease, 
it will be proper in order to imitate it, that we 
ahould pass the electric matter through a very rare 
medium ; and this is done with a flaak similar to 
tbe following, —U may be made of a common oil 
6asl[, though iutinitcly more imposing if of t'uur 
timci tlie iVLt ; its thicker end has a portion of it 
covered ^v1th tin-foil, anfficient. that wb«u held by 
the band, the gU«s itself may not be touched. The 
neck is fitted witli a brass cap and bad, with a 
pointed wire projecting inside ; this ball sliould take 
ofT, and .^Iiow unilerne:itb it a screw, wi{h a valve 
opening outwards, that Ihc flask may be partly ex- 
hausted of air. No tin-foil is oecescary inside, 
which muy be also qnite dry. 




Es. — To imitate the flunora borealis. make the 
fl^sk dry and worm, partly exhaust it of air. then 
screw on the bull, — hold it by the lin-fuil of the 
tliii'k end, and prr^ent the other to a char^fd con- 
ductal, flashes of a beautiful reddiuh purple light 
will |wrvade the glass flask exactly similar to the 

lunomenon wished lu be imitated. 

7^ following \9 a long tube nf glasn. fi««>d to n 
»ti and furnished witli b cap and hall, and pointed 
«1rc at top, with the valve at the foot. It is first 
10 be fixed to an air pump or exhausting syrinfie, 
and the air partially drawn out; when a «park britig 
pa!i5cd through it, by touching the upper hail by a 
wire coinmnnicatiiig wiih the prime conductor of 
the mMi-biDL-, it pai>ses doun the tube to the fm<t, 
and, accordiug to the density and qunlity of this 
medium, so will be the color of the flasbcs, while 
|h«ir Aivqucncy and briUianry wiU depend upon tbe 
itity transmitted. 




Fkiting Stars. — Whenever the electric flaid la 
at a more moderate height, and in a more coneea- 
trated form, it occa«iinn« those electrical appear- 
ances, known tout as liilling stars or meteors; ihfSM 
are generally considered indicative of rain, and not 
withoat aome cause, inasmuch as rain, bail, snow fw. 
are always produced by any sudden electrical change 
that takes place. 

They may be imitnted by passing a shock through 
a long exhausted tube, similarly constructed to tbit 
described and figurvd above ; but not exceeding lutf 
an inch in diameter. 

JiaiHt Snow, ^'c. — It has be«n said by some, that 
tbe reason rain, Hcc. falls in drops, and still more sO| 
why snow appenrs in light fleecy flakes is owing to 
clec'triral repulsion, as is Bomewhal proved by the 
experiment of the expansion of a fleecy feather when 
driven niV hy an excited tube, and also by the ^nn 
aealing-wax. 

EtiHhtpinkf* — Earthquakes also have probably 
nn electric urigin, they have been considered as un- 
mrnse shucks paumg through the eAith ; the ar- 
cumstances in favor of tl.ia theory are tbe rapidity of 
their pasisoge, the convulsive motion which they oc- 
casion, aud that they are always attended by light- 
ning and other electrical appearances. 

f'lerv Kain.^Thus also con we fax some decree 
explain tbt: fiery rain mentioned in the Scriptures, 
aud by various ancient writers, certain it ia that 
every drop of rain which fnlls during o thunder- 
storm is chnrgrd with the fluid, and therefore con- 
tributes to divest the storm of its fiiry. 

WaiernjtoMt. — The water*flpout^ that wondefAil 
nud territic object, is too eotily exptnined l>^ ' ~1 

nttmciion, to leave any doubt ibnt ifs « 
highly charged state of the air, and we are t:-<iiHiu.> w 
in thiit conclusion, by the means taken tu ili<(pt:u»} 
it, which is by firing cannon and poinUng shar^ 
weaponij at it. 



MAGAZINE OF SCIENCE. 



irA»f*r(W.— Wb*t the »aler-Bpoiit U at seft, the 
whirlwind is on land, a current of the electric fluid 
p»Mmg along and carrying with it the light bodies 
it passes oter. I f tim currents or columo* of electric 
niftlter fall upon a surface of the earth, covered by 

Ra-conJuetine; substance*, auch iw the acorched 
]<U of Africa, the sands are elcYftted, moving 
w witli thr wind, at\d constituting what are 
Bthe mfring piliart qf sand of the Desert. In 
Bf bumjag climes, thr air Is so dry. and at the 
■ame time insolated from the earth, by the parched 
saod, that Urge trmcU of electric matter move almost 
in a pure uncombined state, appearing like a bluih 
in the hearens and producing all the effects of a 
deprivation of air. by suffocating ererr animal ex- 
posed to thfir influence. The Cauiel, the Drome- 
^^lary, and the Ostricli, instinctively bury the noae in 
^Kie satul. and the travellera in the ill-fated caravan. 
PSyj flat upon their facea to avoid being immersed 
in the electric fluid. In this sUtc it occaaions each 
I combinations and decomi>oaitionB that iti effect! are 
■Kit even across the Mediterranean as far as the 
^^Eorea of Italy, forming the Sirocco of Volney, and 
^^^e Siaii>«/n of Bruce. 

Thr foregoing is a synopsis, rather than an ex~ 
pUootion of the natural effects of electrical agency — 
nor I* it. iu the very limited manner in which it has 
been deatribed, to be considered wholly proved, that 
irthqnakej and falling meteors, are attributable to 
his artivf power, — on the contrary, the whole sub- 
Inflection, and close comparison of cir- 
and effects^nd which perhaps a future 
riiuiity, will be allowed us to consider and to 




CHEMICAL ELEMENTS. 

HrnnooKif. 

• 

HTDnocrN was first obtained pure by Mr. Cavcn- 

4bh tn 1700. (t is a colorless gas. permanently 

tlaatir. without taste, and when perfectly purr. 

TrifhoTit ^mcU. It is Die lightest body known, being 

ir< lightrr tlian oxygen, or thirteen times 

u atmospheric air, its specific gravity 

U, and lun cubir. inches of it weighing 

la. It cannot supjwrt combustion or 

>i4j but is Itself in an cminmt degree i»- 

Tcquiring, however, oxygen to support 

_ ion ; it may be set fire to by any mate- 

'tU made red hot, its explodes when mixed with 

ocygca or the atmospheric air, forming water, and 

ll« heat when burning is greater tlian that of any 

vtbcr niatcrial. 

Kx. l.^ v ' Hydrogtn frofn Iron, Sul- 

irJUnr A f*. — Put into a wine bottle, 

- ' - ■ — L.aii--. a.... ^<iiie water, and then sulphuric 

.1 m ijuaiitity to one fourtli of the water ; 

, als will iu a minute or two be covered 

with tiobliles of gas, which will rise to the top of 

the te*»vl. Hold a candle near the gas as it passes 

««af tVom the mouth of the Iwtllc, and by its taking 

Hn U will be known to be oiyccn. It may bo col- 

:.rr with a bent lube passing undor the 

NO potfumatic trough, or by a blaibier fas- 

., i,. .- ..II. ..r the battle. rSff f'l'tj 

'ht water is decomposed, its 

rrrtil n*. it ipacttd upon by 

i.iit of the water, 

- upwards. One 

yl uuu jiddi ;k^ cnbic mchca of gu. 




Et. 2. — 7b procure Hydrot/en from Zine, 
phnric Aeitty and Water. — Use some pieces of iin< 
cut small, instead of the iron in the la^t e-\prrimml 
and a tolerably pore hydrogen will be rapidly libe-i 
rated<^it may be collided as before. Ttii» c[M9 
often called hydrorinctc gas. it holding minut 
portions of xinc iiuspended iu it. One ounce 
xioc jrields 67G inches of gas. It is produced more 
rapidly in this manner than in the former. 

Bx.Z.'— To procure Hydrogen froini Water. — Pi 
an iron tube, or gun barrel, upcu at both eat 
tlirough a Are. Make it icd hut. and to una en 
fasten a retort holding water — make this water hot 
by a lighted lamp being placed under tlte retort, 
that the Btcam may p^sa through the red hot iroi 
tube. In this transit it will be decomposed, tha" 
oxygen being absorbed by the iron, rendering that 
au uxyde, while the hydrogen poaacs Lhrough, and 
may be collected at the other end of the lubi 
wrhich ought to dip ander the nirfaco of vatei 
that the gaa may be cooled and purified. 



It 
OTJ. 
the 



Ex. -I.—A porcelain tube, filled with igni 
charcoal, will no lesa decompose water* hbcratt: 
the hydroj.^en; but in this cxpcriracnU corbo 
acid f^as iu"isinp from the rbarcool, alsi^ passea o 
and thus cunuminatcB the pas, until by loim v 
tact with water, the cirhonic acid is absorbed, ani 
the hydrogen remains. 

Bx. h.— Destruction to Animal Life.— \>to^ 

smnll animal into u jar of hydrogou, and it will 
instantly deprived of life. This appyars <o ar 
not from any dclolcrious property ot iltc gas, 
merely owinii to the oon-cxislence uf uxygm 
mixtures of hydrogen and oxygon arc rf^pirabl 

Bx. Q.— Effect OH the f'bice wAen Inhaled, 
Fasten a large moulh piece or wide tube In 
bladder, hlled wiili hydrogen gas. put it to l 
moucb. and slopping the uo«trils, inhale only 
hydrogen, and the voice will become shnllt hi 
then be coiuplrtely lust fur o short time. This 
supposed t^; ari^e, bfcause on account of the 
treuie touuliy and lightness uf the gas, it has a 
sulTicieut nnunenlnm ti. effect the organ of Suuu ' 

Ex. 7. — Gtldint; SUA, Ivory. S^c. hy Uydrotjen. 
Inmierse ii piece of white antin, ^ilk, ur ivury. i 
strong -Riluliou of nilru-niuriate of gold. While 
substance is slit! wet^ immense it in njarut'hjid 
gen gns, it will afler 8onie tiuio be covered b: 
complete coat of gold. Tlie hydrogen in this 
periment decompoBee the oxyde of gold, which 



MAGAZINE OF SCIENCE. 



the baae of the salt, appropriating to itself the 
oxygen, and suiTeruig: Iho gold to be dcpv>»Ued tu a 
nietaUic itato. 

Bx. fi.— Producing GUI Ftovert, ^c, on Silk 
or Iw>ry. — The Ibn^going expennieiit may be 
varied a* follows; paim fluwere, &c., ou iheBJlIt, 
with ihi: nilro-iiiuriate of gold, and tho aid of a 
very hue cniiiei-hair pent-iT. Huld iho silk thus 
painted, over the buttle in which hydrogen is being 
libeniiud; in A short time, the flowers will shine 
with tHJiiAiderablc brilliancy, and will nui Urui&h 
Upon expusurr to iho air. The tliickuew of the 
eoaliiig ti^ gold id not more than the lU luilliouth 
pari of iiu inch. 

Br. 9. — SUveriag by Hydrogen. — Inimeree a 
white silk ribbon, in a solulion of nitrate of silver, 
and while wet, expose it to a stream of hydrogen. 
The silver will be reduced to a metallic slate on 
the silk. This may be varied, as in the preceding 
experiment. The sanic efl'eci takes place with 
platinum. b«t not with auy of the otlitT metals, 
bccautie all the others hold the oxygen contained iu 
tticir uxydcs, loo teaaeioualy fur hydrogen lo dc- 
compust; ihein, 

Ex, iO, — InJiamm\xhUity of Hydrogen.— Tq the 
month of the buttle, in which the gud ts generating 
(as LB uxpenmciits 1 and 2,) lit a cork which has 
a tobacco pipe stem paiuiog through it. The gas 
will pa!i5 thiough the pipe, and mav be inflamed at 
the lop, forming what has been called the pktlom- 
phiecU cttrtdie, 

Ex. 11. — Hold over tlie bottle in which ibe gas 
is forming, a long tube, itLopped at tlie upper, end, 
which will soon be filled with the gas; wrup a 
haudkerehicl round this bottle, merely to defend 
the hand, and wiLliuut turning il up, — that is still 
vilh its ope-u end downwards. Set hre tu the con- 
tents, A dull explosion takes place, and the hydro- 
gen will be seen to bum away slowly, upwards, 
as eHi h part whou consumed, permits the air to 
come in contact with the next. 

Ex, i2.~ Hydrogen Soap Bubbles. — Blow some 
soap bubbles, tllhng Iheiu from a bladder of hy- 
drogen, funilshed with a brass pipe ; they will 
ascend rapidly to tlie ceiling; if they are inter- 
cepted in ilieir course by a Uglitod candle, they will 
explode with a dull repvrt, and a flatih of yellow 




£r,l3. — Oxygen necessary /o its Inflammation, 
— Let a shred of j>ota»sium, fall into a bottle con- 
taining only hydrogen, and a little water, and the 
gas will not lake Gre. This may easily be tried in 
the bottle in which hydrogen is bcuig formed, (as 
in experiment 1 and 2,) but if a portion ofcommun 
air bo present, explosion eniucs, therefore (rreat 
caution is necessary in pcrlbnningthe experiment. 

Ex, 14. — Sot a ntpparttr of Cimtbvution. — Into 
& jar of hydrogen, immerse suddenly a. li^'hlcd 
taper, and although the gac> itself will be iiifinmed, 
the flame nf the taper will be extiii(!:uished. and by 
DO [II ' ' "I it he thrust duwn into tlie gaai, anil 
rcii '^howinp that lhoni;h combuatibic, 

hyu:^.-. .. ... ...-1 A supporter of combustiun. 

Ex. 15. — OiyiftM ojipfOfyi Ui Burn. — Fasten lo 
the top of a bottle, where hydroii;en gos arises, a 
tubd of gloas, ahapcd Uk« a syphon, one leg of 



whteh may be about an i-v '^ - -- • — *■ -- * - ^jif 

tu diameter; plaee thin . i-^ 

hang down, parallel to i:, - m 
can only issue into the atmosphere at ihc tow«t 
end, where being hghted, it wil>. if (he tr»3 ha 

abundant, continue tu burn •■ '■ Ue 

tlame ascending into the tul > .it* 

burning, thnisiiutu the tiame. .mi. :i« 

the body of the gas abuve, a ftnc tu' .-h 

oiv^en is issuing verj* slowly, ihi- .q 

will appear to burst into ilauie \r. it 

comes near, and to bum iu tlie lui : hy- 
(Irogcn. 




This is a very singular expsrimeul. and it vobM 
appear as if the oxygeu were tlie combustible, and 
the hydrogen the supporter of the combustion; b«t 
the fact is, that hydrogen bams in .the midst of 
hydrogen, without inflaming that around iu lh» 
combusiion betnj;; supported only where it meata 
with llio oxygen, Uitu it burns in a lilm of exacUy 
the shape of the Jels issuing into it. If the Jet of 
oxygen be not extremely minute, an exploair* 
mixture of the two gases is very liable lo be formed. 

Kx. 16. — F.ff^l of Water on Burning Hattst*. — 
Water thrown ujion a huuse when ou tire, if not in 
over-powering tjuantity adds to the mischieC M 
the great lieat decomposes it ; its oxygen and hy- 
drogen boili aiding the combustion. 

Ex, 17. — Light and Heat qf Inflamed HydrogetL 
— In the above experiments, where hydrugoii 
bums, the flame is lilueish or yellowish, and ao 
faint, as in daylight to be scarcely visible; it ia 
however intensely hot. To test this, hold a tine rO<| 
of glass to the puint of the flume, and it inslanlly 
becomes red hot, and may he blown or beat tnany 
shape ; a candle, piece of paper. &c., instantly 
lakes lii^ht if held to the fine jot issuing Irum the 
light bottle ill the last experiment. 

(To be continued.) 



VARNISHING. 

TuEBB is no art wliieh adds so much to the in* 
crease of beauly of manuf.-icltired articles as 
vnmishing, if we rcmcmher, thai every liquid 
which comnuinicatcs a permanent gloss (o iho 
arliilcit is washed over with is a varnisli, and ihat 
therefoco lackeritig, waxing, h'rench polisliing, tho 
laying on of glazes, and many other prure^cs. aio 
but modifications of the art of varni^huifc, jls ex- 
tent, and general applicalian, will be nppareut. 

Vaiutflfaes are made by dissolving '■•■'■' i ihn 

gum» and ri-^ins in oil, turpentine or .t 

according to which of the roonairu.\ i . . U 
BO the vamiah is called oil vamiahf turp«oiine vac 



MAGAZINE OF SCIENCE. 



10 wll it'll III" 



t'l 



Cut t» 

ir- 
W 



nifcLi kikI nuLtil ¥uiush. The Ibmer kind huM Uie 
!y, the linl dry the (juirkt'st. 
tip are the modvs of prcpaimtioa of 
' t M'^' hil kiii'lj, irith the puTpoAM 
'.^- ^ i. r:iUy applied. 

' . f'iolinMf ^c. — To n (rallun 
.ii<?, add six ouncfs ol pjni 
^ ,.iiii> uf glim mutiih. and half 

(1 ■' ramish. Put the whuK- into 

a ' ' ep in a»iirm place, frequently 

•h&kLtig it, (ijt twelve days, until it is disaoUed, 
Uxea 9tratn, und lieop it for une. 
Tq makf Caoutchouc FarnUh, 

16 ox. of cnoutchouo. or eliutic reain. 
\^ 01. boiled liuseed oil, and 
!>> or- of ewcncc of turpentine: 

,))t.-li<.uc into thin slip?, and put them 
iL-cd in a very hot sand-bath. 
i^ liquitivd, add the Unseed oil 
L'tilhaon, and then tlic csaoiice warm, 
rniiih has lost a ^reat port of its heat, 
i;*h A piece of liiicn, and preserre it 
iu a widf-iiu'iuhed bnitlc. This varnish dries very 
yt'*t>. iv ,. I ,i!i which is owing to the peculiar ua- 
«i!: i'mtchooc. 

ion of air balloons led to the idea of 
icchouo to the composition of varnish, 
-iiry to have a vamisli which shonid 
i.ibllity fliod consisteucc. No varnUh 
'lie of correspondinfT to these views, 
! caoutchouc, butiho desiccation of it 
•. tedious. 

•i'lahle famish /or l/mbreUas.-^Takt 

«.: of caouichouc, as ten or twelve 

CM ' into ^mnll bits with a pair of scissors, 

and i^ut adiKHigiron ladle, (ttuchoA that in which 

jrtrrtfM. pUimbcrs. or glaziers melt their lead) 

*^ ' >ii pit-coal or other fire ; which nuwt 

b> ^^ infi, nnd without :imokc. When the 

\\ '• ' -^ -'■ :Tle bit into it: if black 

SI.. '.itly flame and disappear, 

•-I :i"ul flame* the ladle is 

huL When the lad In is leiis ho^, put in a 

i»ii. which will produce a white smoke ; 

.vill continue dming the opera- 

ihe caoutchoTu* ; therefore no 

-.. uut little hiis are to be put in, a 

till the whole are nieitcd ; it should 

■ ■. And (;*'titly' stirred with au iron or 

■)'jn. The in^taiit the smoke thunpcs from 

■ HUfk, dice oiT the ladle, or the whole 

I into a violent flame, or be spoiled, 

must be taken Uiat no water be 

' '•- only of which would, uu ac- 

ibiliiy, make it bull uver furi- 

>t noi.-io ; at this period of the 

iidn or 1 f)uari of the best dryinfi oil 

I'jthemelied rauntchouc, and stirred 

d the whole poured into a gta/ed vessel 

coarse Rsuxe, or wire sieve. When 

clear, whicb will be in a few minutes, 

UM', either hot or cold. 

k shfnM be always stretched horizoBtally 

pTns or ttfnti-r4iook« on frames: (the greater 

I- IT'' m I'Ti'-'h the better.) and the ^mtsh 

^lot weatAer, and Aot in cold 

!.ap9 best always to lay it on 

I lie art of laytiip it on properly cou- 

-' BO intc«litie motion in the varnish, 

.!-.■.->' /> niinute bubbles, therefeire 

i are tinpropi-r, as each bubble 

1 forms n small hole, through 



Vki&h Uu) air will transpire 



Fttmiah/or Wateh-CoMS, in imiiation of T&r- 
loise'theU. 

6 OS. of copal of au amber color, 
1( oi. Venice turpentine, 
24 ot. prepared linseed oil, and 
6 ox. Bsseiice of turpentine. 

It is customary to place llie turfientino over the 
copal, reduced to small frapnents, in thebuttont of 
an earllim or metal vessel, or in a maltrasii expv^cd 
to such a hcftt as to lii|iiery llm cupal; but it tJ) 
more ndvauUBCuus to liqaefy tlie latter alune^ to 
add the oil fh a state of ebullition, then tiie tur- 
pentine liquefied, and in the lust pince, the essence. 
If the varnish is too thick, fume csjiencc may bo 
added. The hitter liquor is a rcmilator for the 
consistence in the hauos of an artist. 

To make a Colariat Copal Vaminh, — As all 
copal is not fit for this purpose, in order Iu ancer- 
lain such pieces as are good, each must be taken 
separately, and a single drop of pure es^entisl oil 
of rosemary, not altered by kcepinx, must be let 
fall on it. Those pieces which suften al the pnrt 
that imbibes the oil are good ; reduce them to 
powder, nhicbsift throuKh a very hnc hair-seive, 
and put it into a glass, on the bottom of wlitch it 
must not lie more llian a finger's breadth thick. 
Pour upon it essence of rosemary to n similar 
height ; stir the whole for a few minutes, when the 
copnl will dissolve into a viscous fluid. Let it 
fitond for two hours, and then pour gently on it two 
or three drops of very pure alcohol, which distri- 
bute over the oily ma.Hs, by inclining the buttle in 
dilferent directions with a very gentle motioa. 
Kepcat this operation by little and little, till the 
incorporation is etfeoted, and the varnish reduced 
to a proper degree of fluidity. It must then be 
left to stand a few days, nnd, when very clear, be 
dei:ante(] off. This vnniish, thus made without 
heat, may be applied with emial success, to pasic- 
bunrd, wood, and metals, ana takes a better polish 
than any other. It may be used on paintings, the 
beauty of which it greatly heightens. 
Oold-cotorcd Copol I'ftmtsh, 

1 oz. cnpfil in p"wdcr, 

2 ox. essential oil of lavender, and 
G uz, essoucc uf turpentine. 

Put the p>t<.cntial oil of tavoiidt:>r into a mallrass 
of a proper ^ixe. placed on a sand-bath heated by 
an Argand's lamp, or over a moderate con.l*Are. 
Add to the oil while very wanu, and al several 
limes the r<ip;il powder, and itLir the mixture with 
a stick of wliiiu wood, rounded al the end. When 
the copal h IS entirely dinappearcd, aad at throe 
diffcrcht times the essence almost in a slate of 
cbutlitiun, uiid keep cuiitinually stirring the mix- 
ture. When the sululion is completed, Ihc result 
will be a varnish of a gold color, exceedingly 
durable and brilliant, but less drying than the 
preceding. 

Oimpharated Copal yarniah. — This vamtab is 
destined for articles which require durability. 
pliAblenoss and tTanspareiicy, such as the varnished 
wirc-gau2e, used in ships in^jtead of glass. 
2 oz. of pulvcrixed copal, 
6 oz. of essential oil of lavender, 
^ of an oz. of camphor, and 
essence of ttirpeniine, a sufGcienl quan- 
tity, according to the consistence re- 
quired tu be given to the varnish. 
Put into a pliial of thin glass, or into a small 
mnttrass, thcessentiiil oil of lavender and the cam- 
phor, and place the mixture on a moderately open 
Are, to bring the oil and the camphor to a alight 



MAGAZINE OF SCIENCE. 



■tAtc of eliuUiUou ; than adil Uie copal powdar iu 
nnnll poriloiu, vliich must lie renewed tu they 
diftftppear in thr ti'juid. Favor iho Boliition, by 
contuiunlly slirring it with a filick of white wood ^ 
fttid when th« copal is iucorporaU'd with the oil, 
add thuessencti of turpentine boiling; rhiitcntunnist 
lie iHkeii Iv pour in, at first, ''[ily usinall purtion. 
This vamub is hltlo culored. nnd by tt'si it ac- 
qtiinrs » transpRreacy which, united to the solidity 
obstirved in almost every kind of copal ramishcs, 
renders it fit to be applied with grcnt success in 
many caseB. nnd particularly in the ingenious in- 
Tcntion of substitutinp rarnishcd tnctAllic gauze 
in t)io room of Muacory talc, a kind of mica, in 
hr^c lamiDir.nfled for the cabin windows of ships, 
OS presenting more resistance to ilie coucuMsion of 
the ftir during the firing of the guns. Varnished 
metallic gauie of this kind is maDufaclurcd at 
Rouen. 

Ethereal Copal P'amigA. 

^ or, of amberry copal, and 
'2 !>«. of ether. 
Reduce the copal to n. very fine powder, ttnd in- 
troduce it by small portii>Ti8 into the flask which 
contains tlie r.thpr; clow the flask with a ^loss or 
cork, stopper, and Imvinr shaken the mixture for 
half an bour. Ic.ivr it At rest till the next morning. 
In shiikini; the flni^k, if the sides become cnvered 
with small undulations, and if the liquor b« not 
exceedingly cleiir, the solution is not complete. In 
this cose, add u Itttle ether, and leave the mixture 
at rest. The Tarni-th is of a light kmnn color. 
The lariirft quantity of cnpitl united to ether mny 
be a fmirth, and the Iraal a fifth. The useof copnl 
voTtiish made with ether seems, by the expcnso 
Attending it. tn he crinfiijed to repairitin iJiose 
Accidenle which frequently happen to the enatncl 
of toys, as it will supply the plate uf ^lasf (o the 
folorcd varnishes employed for mendiufr fracture!*, 
or to rcst-jfuip the Bmooth surface of paintings 
which have been cracked and shattered. 

(To be continued. J 



MISCELLANIES. 

Conxumptnnt vf Smoke. — Mr. Hwlda has pa- 
tented a mcuns of conaiiniing 5aiokc, by means of 
pnrtin^ ufT a purtion uf the batk of u furnactf 
Hilh firir-bntk. »o that when tbo coal bos bn-ii 
coLeil in ihe fori*part, it is thruit into the binder 
division; and the smoke from the freely-suppltcd 
coal bi'iug made to pass over ihu iuc4iuiiescent 
cnkrtl fuel, i» <oniiimi*il. The principal mrrit of 
thi^ iiivrotitm \h it> »iro)i1icily ; coDkivting merely 
iif * frw fifr-brirkf, «hif h mny be plufod in itii) 
furnucQ H'itliuiit expensive ;i]terutiou. 

Lnr^e Sheft of Prt^er —There ha* been lately 
sent fiom the manuructnn- nt Colinton, a Muglv 
iihret of paper, weitrbing533pi>Mn(ls,anil meoauriiiK 
u|)wuriJa of a mile an'l w half in Icnpth ; the 
brt-adlh bpinjt only 50 inchci, Were a ri'am of 

pap»-T ' ^-I of similar •hceit made, it would 

wci- [.niin"l>, or iipw.irdKof 123 tons. 

Mi- .»i7ene/io«.— Take a page, or any 

olbri tl. tihiie poftiuu of printed paper, cut* it into 
two pirr*'i, Qote Ihe %ixt of the type, and place one 
piece a«i>lr as the mn«leror lest. Thrust thr other 
piece between the ban of alighlcil ^rale, or iijniie 
u iu uuy other manner which may be prefcrretl; 
place it genlly on the hearth, and let it burn away, 
till entirely consumed. Take np the paper so 
t'hflirvd eaiefully., and, huldinf{ it to a ^ood light, 
the »ixe of the print, which it ^)erfectiy legiMc, 
VjUbc found to have become (.onjidera'ily reduced, 



villi* chv sh«i'i'»n>'« ■•' tinr.tv nf Ihe ii 
will have h« ■' neif. 

The JNih <' iiijicars from the IriiiSi 

|iu pen, thai guicruuicul h^vii given their »anct)oa 
tu the worLincof ihoseiuiiica, which have at vu-toua 
times excited the atlfntmn of nuaiug adventurer* ; 
and we are led to believe, frum iuformation whieli 
we have receivcil. that gold may be calculated 
upon beinff found iu quantity. 1'he gold dintrict 
extends over a space of leu square miles, in a half 
circlet roond the Crojihan mountain; aud gold baa 
been found in the sirfains flowing from the difiemit 
springs which ibts district gives rise to. Every 
flood carries down some portion to what is called 
the common stream, whither the peasantry useil to 
aascmblc to gather what they coold. Large picccf 
uf magnetic ore, and other substances, have beon 
found, denoting the extraordiuary metalliferous 
properties of the country-, ond iJie analogy whteb 
they bear to the gold country of South Arn^rica tB 
remarkable. This work t» now in prop-ess. but 
wheUier it be tlie intcutiou of the parties to irork 
it singly, or oa a joint-stock concern, we know not. 
(JoM is now. we are given to luiderslond, beiug 
raited, BUfl the Work of discovery in progreia. — 
•1/i»(Nj/ Journal. 

QuiRIES^FRoifvOLT 

13!^— Ilnw tirp ttn.l*! rtUtrr nl'-r* (i.n.l.- ' 

14V— Wlint l« 1 

tWi — How art 

Ifll— lloiY ore 

fAT— H,,vr o^^ i , picparad? 

ICfi — Hnw lir«' 1 

I7t— Howa-: 

ir-i— H 

\\»Vl\ MB .1 ' .... 

scofchtfd by ruf ' 
I HO-Whut II Uie caUM of Bbnt, i|nttlon. and radistton f 



■■li bleack»*l 



QTJ 



[JERIES. 

)S!U- What t> bornru) poliab. and it« prefHintioo^ 
)S6— How ts printinu 11) gi>t<l p«rtant»r4} Also. Ihp ma 
bertaJK tor e^vlorcii prmlitti: ink* ? % 

187 — I low ii ()ii> tSunilpr. U)(titning. rain. hojl. and wiod 

of ttit OirUfrv* |rnK|U(ft] * 

IW — Whitl i» tiic liol fly rwl tor f>ri(omi>lr^lca) fwrpovvf 

IW — iivvr Mc in>«(> III cabinet* twtl pri*i>orvei) * 

Ijn — IK>«N mo.-niltiilii url in wjy nay upon vt^claUoo? 

191 — \Vlt«l \» til*" prDrt>» of rlc*iiillrii; fun' 

IV'i— Wliiit ciku»c« the difTemil ci^lora In tJi« nam* ot « 

C4llllll> ? 

I'JI—IIctv and of what material aivMci'rahsni |M|wi mtds * 
I'-'l — llou are t)K> cnraniftn ttpV» wnler color* made ? 

CORRESPONDENTS."^^" ' 

Unuv Rt Ktint.^tn ihe [wii-ol IikIimd ru^hr- -■■-'-;- 

intxnl nUh tfio tjcnmne arurle It i« very ' 

itnjiOMtblc. fok(]ullcrii1« iTauuU'hi.<up,tW>uu>< 

in <|it4llt} 
Ki sx»t'i» »-« will t>inir in milid. 
l*iriio-cnxw)ei.«,— No doubt ynu ar« corracC ai to tlie llioe 

an>l rlMnx'u), 
A ]>Aiiti>R IN OniMiiTRv.— Tb* artiile b« alludas to la ta 

|irtftmrutliin 
J HincMtY — SiMOaygen in last volanw. and tlydraven ia 

pivMid number 
J W. II— I'ul 111* paintinHilonnonn flal*urrn<'«. stMlRJue ■ 

I'li^r l^t tllltiruiwi.- „-...nM.- I1....L- ..r i,,n, mMcly WSihtOS 

the burk ul It u ,tkll b« beneot'iiil 

W W— J. H. A I 

J Wii*<j«.— WpkIi ;._., ., :u^*u|ue•nnn. amlRm 

lbs ilViiirtiaiom Niid nuiti>r;.ilii of luch in«lrumen1a a» w«i 

dvKtIbc. where nccMtary for the iintRlvtir. 

CommunleaUoa*. Bwks for Keviirw, InvenUona for llliu. 
tr«Uij». lie . I» b« oddrt^Mrd to ths Edllnr. at M, (trvot 
Pnicol Street : to the* Printer ^ or to Uie PuMiaJwr, All 
Letttrs muat be pest paid. 



Priatrd by P FaANCit. fi. Whlti* llnr>« Ijin* M 
PubUUitfil eM'ty ^»lt'^^■ll^y lis U Umitiaiji, i 
Ri)W. nnd m-is hf ti.i.l <*i nil [luukM-iirn ui>.i 
Town and Cxiiiitr) 



THE 



MAGAZINE OF SCIENCE 



^n& ^tt)ool of Mm* 



No. UV.] 



SATURDAY, APRIL U, 1840. 



[Pbxob IH 



Fif. 1. 




Pifi.2. 




TURNING.— THE ECCENTRIC CHUCK. 



vou a. 



m 




MAGAZINE or 



Okb of the most atofii] apprnJai^ to an amateur's 
Utbff it ihc Eccetitria Chuck. Its particular pro- 
pcrticu arc tu msble the tttrner to alter the ceotre 
of hii «orV at plrasDre, thus the work produced 
tihibiti a beiQtifol intormixture of circular Uqcs, 
or omamentit, and whirh rnnnot be produrrd hj a 

trammon chock. To illttntrale this the two following 
rat« rihibii the propertiea of the common and the 
t«e«n trie chuck. 
Mtlli 





to 



In Ik* Bbo««, the Tarioua line* art alt around the 
tnta* centre, and conf«iucnr!y of different lizea 
thmiiKhout, (thtir »ifc and diitart r frum vih 
atbrr drprnda upon thf pontion of th« tool and 
not «pon tb« chnck.) In the next illujtration, there 
■ra tliree ((roQpt of rqoal sized rirclea, at eacti imic 
In every rroup I* from a ditfrrent erntre, nol 
any «n« of them a|rreitis with the centr* of the 
«hn)e, though the nrroupi arr » ';■ f«jui. 

dittant froni it. In thr inn?tt >re nit 

oiroUt* la 1^ tcatie one i"*, «' ' r row 

32. 




11ie dearriptioo of the cbnck wbieli p«nua fMb 
Alteration of adjuatmmt aa to occaaioa Ihis MM^ 
tricity, ia aa foHowa : 

Fig. 1, ia a repreicntation of the eeoentrie chock* 
seen when looking at ita boe ; fif. 2, thamt Iht 
iara« apparatus. 9e«-n sidewaja. The a«me Uttm 
refer to both. 

A A ia a plate of braai, a quarter of an infh tt 
more in thickness, having a screw at the b*ck of U, 
•era at O in fig. 2. bj which it ia penm^ on l» 
Ibe mandril of the lathe, in the same atMiiMr «• 
other chuck would be. B B are two alidsw of 
screwed down to the iorfacc of A A, by two 
In each, the holes (hat admit the 
B B being a little oval, in order that the slide* 
be adjusted, so that they may aiaaya p««i 
■fainit the inoer slider l3, and be perfect 
to each other. To prraerve them in thi 
position when once tixrd, there are fosr 
C C C C, whtrh "crew into four stud*, left pi 
nenily ^: ! .t-an the face of A. or elM 

more u- .^e, the sides of A A which 

Jett b«) iu, t-lidcj B B, are cut oir. and 

the acrrvftt C C C C, are tixrd in the side* of 
prnmtitt?nt he^ds of thciii ouIt t»earitig acaixwC 
r> is a plate of brasj, which ia made to 
fntoothW brt*f^n ft B ; it hni upon tfa« n 
U a »lt ',. 9f. trrih, 

aprinjE .! .-.t G and H. 

whrrl ] . . jinir I>. and is so faal 

tli..f 1- 1- I'.. 1. '<■ '.ltd, and yt't not oat 

pi '■■ . '-■'■•■ ^i\^. .i.-t nSuir ...11 tSi!,.-i aothatk' 
not hhnke in its bed or b- lie l^onC of 

tiK'llii d wbrf! hnn aluo a •^ ; >t, of lb« 

' ■"«I ' '1 -I ■ ! Oic ntanilrU, «'«ii in shadow 

1 ■, .1 'h, luiial rommon chucks ai 
■iMrhfd. i'ht i-rritUr ii4ivitmeota of tbo 
wiirvl wiU b*' fT lirnt from I 
Ihr figarc. Tbc Utrral motioo of the 
1>, is ocrtaioned by a screw towanls tb« 
rr prr^rntrd nT I. This acrew ia made with mj 
o< ' ' the hich- it is 

*i '-itT 1. by meaas fit 

thiiniit an<i nfigrr, nr a small handle to 
and un at ncfa adjn^tmrnt. The 
fcmlshrd with a micrometer bead dividad 
porta, for the sake of such oiiniiu ahan 
■lay be naeeauiry, a stud V, abows tb« 
lh« aonw pasaed overi alao Che whiwt E. ia oom- 
ber«l aa every twette toelh. by the fifuraa LS, 1^, 
3G. &c.. up tu 96. 

Wb<m tite screw I ti in ona poaiUoa, tho 
axacUy oorrasfponda to tha contra of tho ta 
all Um drdea ouda ar« ooooeotrfe, aa tai 
the Ural.— If tha tool b» art to ao txtnm 
dtotanoa fkwn Mm oaom it wUl make a ami 
ol a %imUm diMMMa a la>f«r drcia, asd ao 
Kow a Bp poaU t II beaat aooacmihoibaef 
aw a llf s l , drctfl la etampla 3, and tho 
tonifld ooce roood, to woold poah Iha 
^nwm 
OM of Um alivte la tho li 
3» MhrtHthoM 

Iha whoal B tooad It 
■Mka a aaeood eiralo, ton U 12 MOto mHu 
«4U maU a ehiid airdo ayi dtalaot aod of 
i«M to tho Ant, thw maiiod ^^^t dn^, «M 
li aaao will Umeb oaa aaoCbar. In tha 
mtanrn aU tha olhara an oMda. If 1^ 
ho ao odtoMsd «a to Mk« o hffe cMo. 
the thna |nrapa of asnoiple 1, iha itoria 



MAGAZINE OF SCIENCE:. 



U 



r ^'-^ -ither. If the iw)\ be allowed to cut 

; icfid ennctly tu the centre, it acti 

::d cutj a white dut, a» ia the Urger 

pU beluw. The tooU employed fur t h\9 kmd 

wark, u well ti the srauU slide rcAt neoe«Mi7 

iSinr adj'utiurut, w« aUall priipai> ^a ftrtifiie 



npon, and cinUio more fally the txturd uui 
mann^ement or ecwutric work. 

I'bc foiiowing 15 giveu u m general lUtulrntluu uf 
the character of it, which Lotrever may b« KibJii«4 
aud varied niUiuiit aud. 




?HOSPUOHIC MimsORS. 

Sows attribute that luminou* aijpcaraticc which 

rs bj the aame of If^ais Patuus ti> putrerictjoa. 
U obaerred in bnggj pUces, and near river*, 
tkoafb »ocaetiaie« also in dry placts. By its ap- 
:, benighted travelleri are said to have been 
ifctlnet mitled into marshy plaeei, hogf, and 
quaguires, taking the light which they saw before 
tlkexn for a candle at a distance. Prom this seem- 
tn^y miacbicTouB property it has been thought^ by 
ikt ralj^AT, to be n npirit of a raulignant nnturc, 
aeoordiogly, Wiii-ufUh-a-iouj}, qt Jack-wUh-a-fan- 
ikorUi for the same reason &Uo it probably bad it« 
l^dn tULfoe, JgniM Fatuui. 

ThiN kind uf liKhC ia laid to be freqaent abont 
kttrying places and dang hills. Some countries are 
aUo remarkable for it, aa aboat Bologoa, ia Italy ; 
aad aome parta of Spain and Ethiopia. Dr. Shaw, 
ilhu Trardi to the Holy Land, says, that it ap- 
|nnd io the valleys of Mount Ephraim, and 
iftwrftal hhn and bU company for more than an 
how. Sometiniet it would appear globular, or in 
the fehflpe cd the flame of a candle — at otliers, it 
vvfild spread to such a degree, as to involve the 
«kttle company in a pale inofTensive light, then 
wot ran lUelf, and suddenly disappear ; but in leas 
Amo a mintile would appear again ; sometimes run- 
iring tmitdj along* it would eipand itself at certain 
over more than two or three acrca of the 
It motmtaina. The atmosphere, from the 
of the evening, had been remarkably 
aod haxy ; and tlie dew, aa they felt it ou the 
«f tbiir horses. ««b T«ry •lamny and 




Ughts, resembting the ignia fktuus. art some- 
times to be met with at sea, skipping about cht 
moati and rigging of altipa ; and Dr. Shnw informs 
us, that be has seen these in such weather as that 
just mentioned, when he aaw the ignis fatuu- in 
Palestiue. Similar appearances have been ohaerv»d 
in various other situations ; and we are told of out 
which appeared about the bed of u woman in Milan, 
surrounding it, as well aa her body, entirely. This 
light fled from the hand which approached it ; but 
waa, at length, entirely dispersnl by the motion of 
the air. 

These meteors are now considered as real exha- 
lations from the earth, produced by gas, vapour, 
or some other attenuated substauct.-, emanating 
from vegetable, animal, or mineral matunols ; and 
combined with the niaiCcr of light or hcut. or liotU. 
Instead of being dcii»c ur sulid, they are uutformlf 
rare and subtle ; and. instead of originntiiig in tlia 
loftiest rvgiuns of the almoipbere, or beyond its 
range, are geaerated. for the greater part, iu luw 
marahy plains or valleys. To the fearful and supor- 
stitious they are a source of terror. 

In Italy, in the Bologn^ae territory, tbeyaresi* 
frequent, in the moroMsy grounds, that they era Iu 
be seen every night; some of them alTordin^ aa 
much light as a kindled torch, and oihcrk not being 
larger than the Aame of a candle, but all of tbeai 
ao luminous as to sited a lustre on the surroaodiog 
objects. They are constantly in motion ; hut this 
motion is various and uncertain. They sumetime^ 
rise, and at otberH aink, occasionally disappearing 
of a sudden, and appearing again iu an instant in 
some, other pUcc, They usually hover about ii\ 



n 



MAQA/INE OF SCIENCE. 



feet from the grouDd, diiferiog both in figore and 
sice, and spreading out and coutracting thcmselTea, 
■Iternately, Sometimes they break, to appearoace* 
Into two parta; ioon after uuitiiiK again in one 
body ; and at iotcrralj flout like wav ea, letting fill 
portions of ignited matter, Uke spark* from a tire. 
They are more frequently observed in winter than 
ID nmmer. and cast the strongest light in roiuy aod 
moiat weather. They exist mostly od the banks of 
brooks and rivers, and in morasses; but are Like- 
wise seen on elevated grounds, where they are, 
however, of a comparatively diminutive siie. 

In the month of March 1728, a traveller being 
in I mountainous road, about 10 miles south of 
Bonania, perceived, as be approached the river 
Rioverdo, hetweca eight and nine in the evening, a 
light shining very brightly on some stones which 
lay on the banks. It waa elevated about two feet 
above them ; Its figure describing h p&raitelopiped, 
more than a foot io length, and about six inches 
high, its longest side lying paj-allel to the horizon. 
It* light was so strong that he could distinguish by 
it, very plainly, a part of a neighbouring hedge, and 
the wnter in the river. On a uear approach, it 
changed ^m a bright red to a yellowish color ; and 
en drawing still nearer brcame pale ; but when the 
observer reached the spot it vanished. On his 
fttepping back he not only saw it again, bat found 
that the farther he receded, the stronger and more 
luminous it became. This light was afVerwsnls 
Been several times, both in spring and autumn, 
precisely at the same spot, and preserving the same 
•bapo. 

On the 12th of December, 1776, several very 
remarkable ignes fatal were observed on the road 
to Broma^rove, five miles from Birmingham, a 
little before day^li^ht. A^ great number of these 
lights were plnylng in an adjacent Add, in different 
directions; from some of which, suddenly sprang 
Dp bright branches of light, rr^rniblinglhcexptoRion 
of a rocket, filled with many brilUnnt stars. In the 
esse of the latter, the discharge was supposed to be 
upward or rertical, instead of taking the usual 
direction. The hedge, and the trees on each side, 
were strongly illuminated. This appearance con- 
tinued a few seconds only, when the ignes fatui 
played ns hefure. The spectiilor was not sufficiently 
Dear to observe whether the apparent explosions 
were attended with any report. 

la the month of December, 1693, between the 
7-lth and .^Oth, a fiery exhalation, without doubt 
generated in the same way with the meteors de- 
scribed above, set Are to sixteen ricka of hny, and 
two barii)* 6lled with com and hay. at the village of 
Hartcch, in Pembrokeshire. It had frequently 
been seen before, prncerding from the sea, and in 
these Instances la^ited for a fortnight, or three 
weeks. It not only fired the hay. but poisoned (be 
gra&s, for the eitenC of a mile, so as to induce a 
distemper among the cattle. It was a weak blue 
6ame, easily extinguished, and did not in the latst 
bum any of the men who Interposed their endea- 
-fours to aave the hay ; allbough they ventured, 
not only close to it, but sometimes into it. All the 
damsgo sustained happened, constantly, in the 
night. 

Belonging to thla class nf meteors is the ^raco 
VffJlffu, a fiery exhalation, frequent in marshy and 
eold countries. It is most common in sumaier ; 
and, although principally seen playing near the 
Wanks of rivers, or in boggy places ; stUl it some- 



times mounts up to a constderable height in the alr« 
to the no small terror of the amaxed beholders. Itl 
appearance is that of an obloog, aometim'* nmndiih 
fiery body, with a long tail. It is entirely harnslnM^ 
frequently sticking to the hands and clothes of 
spectatora, without doing them the least injury.— 
Thflt cnrioos phenomenon, observed by Humboldt« 
in South America, called the lantern of Maraoaybo, 
is, undoubtedly, onnlogoas to those meC«or» w» 
have been describing. 

To the Editor q/ Me Magasine of ScUnce. 

SiK. — I road with great pleasure an article, in No. 
48, of your excellent Magazine, on the 0x7- 
hydrogen blow-pipe invontrd by Mr, CiumejT- 
I'raly he is wuriny of greni praise fur haTuig \i%\% 
iiilg the himd of iJieexpericnentalisI 90 powerful an 
agent as the lUme of Ihe roixt'd gases. Fur thta 
purpose Dr. Clarke had some years bpfure inrentcMl 
ihc compression blow-pipe, the risk in using it was 
so fearful as practically to forbid ila adoption. 
But however vast a sirido was madu in the cua- 
struction of Mr. Gumey's instrument over the 
furmcT plan, room was still left fur furihor tm* 
provemeiit ; for in usmg this blow-pipe, if tha 
preasurc on the bladder be irregular, the flame jjs 
apt to recede iliroiigh the chamber of wir« game 
and asbcaioa, and blow out the cork of Ihe water 
cistern; which circumstanre though unatlcnded 
with danger is aufHciently annoying to lendar nil 
vmpruvemeul desirable. This ia iu a great 
remedied by the jet ahovii in 
J^^. I. 




which was invontcd by Mr Hemminps. It con- 
sists of a cylinder about 4^ inches long and 4 of 
an inch in diameter, with a acre^w at one end l» 
attach the bag or bUddor contAining the mixed 
gases, and a jet at the oOier end, throueh which 
the gases issue and are burnt. The c^'linder G is 
filled with exceedingly fine brass wire cut into 
lenglhs, and made up into a bundle, and then 
forced into the body so as to occupy the whole of 
Ihe interior. The pas which enters is obliged to 
pass throagh the capillary passages formed be- 
tween the wires, which in ordinary caaes is snA- 
clcnt to prevent the flame from returning. But 
(his jet is not in every caae safe ; and the risk that 
is always altendant upon having the gases m the 
same vessel rendered it desirable that some olher 
plan should be devised, so as to enable them to be 
kept separate, until they reached the point of 
combuflion. This in part is accompliahed by 
using the apparatus, shown at 

Fiff.2. 




in which the hydrogen passes through the one 
tube, and tiie oxygen through the other tube, con- 
BoquGDtly they do not mingle until they leart the 



MAGAZINE OF SCIENCE. 



13 



itoLntA of Oi« jcU; thus perfect safety is attained, 
put the mixing of the gaara i« nut complete. 

Another plan was lo hare two tubes, oda inside 
tbc other, as shown in 

Fiff.3. 




in which the oxvgen enters at the end and poucs 
tip ihc centre tube, as shown bv the dulled lines, 
and comes out at the jet. the hydrogen entera at 
ihe top aud pasnea outside the oxygen tube, and 
cocnrs out at the same jet a cap is put over the 
end, aud ihe gases paas out as usual. 

This is in substance the jet of Prof. Daoicll, 
and Mr. Maugham. In both the last described 
jets the pascfl arc contained in separate bladders 
«r ba^i which arc connected by flexible tubes, to 
the proper part of the jot. This last though rery 
ccmveuient is not free from dnngor, for if the 
prcssnre on either of the bags is taken 00*. or not 
tq^sal to the other, the gas which is under the 
fi«Atesl pressure will be forced down the other 
tatw, and render tbe contents of that bag explo- 
tkte. This though apparently a trifling thing is 
not really so ; for in two instances within my own 
ICBOvledge. Uie bag thus circumstanced haa ex- 
ploded, aud caused great destruction of property. 

Prom these remarks it appears that to bum the 
gases with safety and yet with perfectncss of 
mixlare, it La necessary that the apparatus should 
be so arranged as to allow the gases to pass from 
the bladder or bags to the jet, but prcTont any 
from retoming. These desiderata arc fully ob- 
lAlB«d in the jet consLrucled by Mr. Pabncr. of 
Mewgatc-«troet, which is shown in section, in 

Ftff. 4. 




TTiecnd A is connected willi one bag or bladder, 
and the end B with iliu other; the gases pass 
through the separate tubes as mnrked. into tt.e 
domW (which is Oiled with the finest wire 
nan and in tilterinir, as it were. throUKh which 
ttt gaoes become perfectly mincled,) and from 
tikMiee to the jet which i* secured into the hole iJ. 
At E B an* two conical \alvcs opcDUig mwards, 



which allow a free passage for the gases in the 
direction indicated by the arrowa, but which frem 
(he nicety of their construction instantly close, 
if there is any pressare in the opposite direction; 
so completely is this the caiu'. ihut the jet may bo 
used for either gas separately, wiUiout screwing a 
cap into tlie other onfice. Thus are we in poe> 
session of a jet, at once convenient, safe, and at 
the same time ensurtng a pi'rfect mixture of llie 
gases, without which n creat portion of the uffcet 
is lost. With hearty wishes fur tbc success Kit 
your Tsluable journal. 

1 remain, youri truly. 



GROVE'S VOLTAIC BATTERY. 

Mr. W. R. Grove, M.A.,baB constructed a small 
battery consisting of serrn It queur-g lapses, contain- 
ing the bowls of common tobacco-pipes ; the metals, 
zioc aud platinum: uid the electrolytes, concen- 
trated nitric and dilute muriatic acids. This little 
apparatus has produced effcctii of decomposition, 
equal to the moat powerful batteries of the old 
construction. Mr, Grove has since tried Torions 
combinations upon the some principles, and though 
some of the rarer substances, socb. for instance. ■■ 
chloric ocid, bare produced powerful combinaiions, 
be has found none superior, and fen- equal, to the 
above. Mr. Grove has, therefore, ecouomtzed the 
materials ; thus, on the side of the line, salt and 
water has been found little inferior to dilats muria- 
tic acid ; and it dispenses with the amalgamation of 
the ziDC. By using flattened porellelopiped shaped 
Teiaela, instead of cylindrical, the concentrated add 
is much economised, the space diminished, and the 
metals approximated. (According to Prof. Ritchie, 
the power is inversely as the square root of the 
distance between the metals.) 

A hastily-constructed battery, upon tliis principle, 
was presented to the Britifch Association. It 
consisted of an outer cape of wood, (glased earthen- 
ware is better), 7^ in. by 5 and 3, separated into 
four flat compartments by glass divisions; into 
which are placed four flat porous vessels, measuring. 
In the interior, 7. 2^, and 3-lOthB of an inch: 
they contain each three ounces, by measure ; the 
metals, four pair, expose earli a surface of 1 6 square 
inches -, and the batttiry gives, by dccorapoMtion of 
acidulated woter, 3 cubic inches of mixed gases per 
minute ', charcoal points burn brilliantly ; and it 
heatf C inches of platinum wire l-66th of an inch 
diameter ; it5i eflfect upon the magnet, when ar- 
ranged as a single pair, is proportionately energetic ; 
it is constant for about an hour, without any fresh 
supply of acids. The porous vessels are identical in 
their constitution with the common tobacco-pipe. 
Its power, with reference to the common constant 
battery, is, e*/ert* parihu*, as 6 to 1, but tbe pro- 
portions vary with the series. The cost of the 
whole apparatus is about 2/. 2i. During the opera- 
tion of this bnttery, the nitric acid, by losing sue- 
oessive portions of oxygen, assumes, first a yellow 
then a green, then a blue color, and, lastly, becomes 
perfectly aqueous ; hydrogen is now evolvod from 
the platina ; the energy lowers, and the action be- 
comes inconstant. This valuable instrumeut of 
chemical research is here maile portable ; and, by 
increased power in diminiiihed space, its adaptation 
to mechanical, and e*ipecia11y to locomotive pur> 
poses, becomes more fe^tslble. 



H 



MAGAZINE OF SCIENCE. 



ON AUSENIC, 

COKTAIXED NATCBALLy IN TUK ULUAll BOOT. 

M. Obf I LA hu re&d a memoir ou the abore eab- 
jec( btiforo the Koyiil Academy of Midiciuc; llie 
experimenU detailed were made with &1. Cvuoibe, 
and their object wai to solre the foUuwiiig 
questions : 

Itt. Does aneaic «zist originaUy in the hutnaii 
body 7 2ndly, Do the riscera contain any ? 3rdly, 
Can ita existence in the mu»clesb* proved? 4thly, 
I« it possible to determine that the arsenic ob- 
tained from a corpse if not that which ori^nally 
existed among: the elements composing the tissues, 
bnt waA introduced into the digestive organs, ap- 
plied to the exterior, ftc. 7 

I, Arsenic exists in human bones; if the bones 
of an adult be calcined, taking care not tu rai»L' 
the temperature too high, and to avoid contact with 
the fut:). these bones, when reduced to powder And 
treated with purifled sulphuric acid, and then tried 
in Marsh's apparatus, will yield brown, brilliant 
and thick arsenical spots. This result was ob- 
tained both from the bones of corpses of adults 
who had been dead some days, or buried fur some 
months. 

When the calci]iatlon is effected at a white heat, 
no arsenic is obLniued, nor is any procured from 
the bouos of commerce reduced tu asoft paste; but 
if they be subjected to heal and lUu nr^L-esses indi- 
cated (nilric acid, potash and sulphuric acid), a 
certain quantity of arsenic is obtained. 

From this ^rst series of experiment, which 
amount to fourteen, I conclude, says M. Orfila, 
]6t, That the bones of the human adult, of the 
horse, ox, and sheep contain minute poitioris of 
arsenic, which it is po«iblr to discover by trt'ating 
the bones with potash purified by alcohol and pure 
sulphuric acid. 

Sudly, This quantity of arsenic is not increased 
by long burial. 

3rdly, Vitrification removes a portion of it, 
which is undoubtedly occasioned by the volatiliza- 
tiun which it occasioos. 

4thly, Among the conditions favorable to the 
discovery of arsenic, must be especially reckoned 
that of not calcining the bones too strongly, and 
secondly to avoid carefully Iht- contact nf fuel. 

5lhly. When bones arc treated with water and 
ebullition, no arsenic is discoveiable. 

6thly. If in operating in thia mode, any arsenic 
be detected, it has certainly been in some mode 
inlrodnccd into the economy. 

It. Ho arsenic is found in the viscera unless it 
has been absorbed. I'hc organs of a dog which 
vas bung, treated by the usual processes, did not 
yield any. l*be blood, brain, the liver, spleen, 
kidneys, intestines, stomnch, &c., gave no traces 
of it. Carbonized with nitric acid, and afterwards 
tried in Marsh's apparatus, white opnque spots only 
were obtained, and these were also produced with- 
out llic presence of these orpanic mailers. 

The liver of an adult gave none; nor did the 
dccoctiuns made with variuus organs yield any. 

From these fuels we may conclude, observes M. 
OrBta, bnt not positively, that the viscera do not 
originally contain arsenic; or to slate tlie fact 
more accurstoly and not to prejudge the case, it 
msy be asserted, that they do nut yield nny when 
treated wiih boiling wntcr, sulphuretted hydrogen, 
or wheucarbonircd by concentrated uilric acid,&c. 
It may ho happen iJiai the quantity is too small to 
be delected by sulphuretted hydru^cu, of that it is 



lost by carbonixallon ; bat by acting on • taifs 
qnantuy of brain or other orTai;s, it may be de- 
tected. At any rate, it is sumcient at pre^eni t^ 
have asceitainc'd, that the viscera yield uv 
by the reactions described, unless it has l- 
troduced by poisoning. 

III. 1 lis not proved that muscular ft«shcoD(aiM 
arsenic ; twelve pounds of it taken from the corpse 
of an adult, carboniied by uilru: a<.id and taetnd 
by Marsh's apparatus, gave w)^!'- i ;.ui .^ *.(..,(. 
some were brilliant, with a b: 

were yellow, and had an ar«i. 
diMolvcd in boilmg nitric acid, tUty ^^*c u^ aIUu- 
ceoos smell when put on red-hot charuual ; in 
fact, they possessed none of the charactc.i ' 

arsenic. These spots were, howeiur, vet 
rous ; submitted fur nesrly ttieiity d^^ 
current of sulphuretted hydrogen gas. iti 
no indicatiun of arsenic. It is possible t < 
were a mixture of arsenic and animal matter, and 
that the muscular flesh of two or three budiee 
might yield some by analysis; lastly, other pro- 
ceases may discover it in the same quantities as 
those employed, by occasioning loss loss; tht^rcfore* 
adds M. Orfila, I will not conclude, positivtlyt 
that arsenic does not exist in muscular flesh. 

IV. It is possible to aflceriain that the arsMiia 
which may be discovered docs not come from t^ 
organic substance itself, but that it has be* r - — 
biued with it by absorption. Fur if it be 1 

the bonos, it will not be removed by lont L , 
in water, unless it had been introdnrnd ; and the 
same holds good with respect to the blood and thtt 
organs which have been examined. 

Lastly, if the muscles yield spots, someofwhioh 
resemble arsenic at tiriit sight, the di^jtinclive 
characters which have been stuled uiu^t be i«- 
membercd ; and if the subject h.id taken arsenical 
remedies, this circumstance ouktht to be p.iritcu- 
larly attended Xo.—~J<mrnaI tie Chim. M»d., i3«r. 
1839. 



PREPARATION OF GOLD-BEATERS' 

SKIN. 

This manufacture requires the previous freeing of 
the muscular tunic from the other nu-i'" 
which constitute the gut. Anatomists di^ 
in it three membranes; viz., the exteri,.., .l-, 
termed the pentontai; the middle one, or musette 
tar membrane ; and the iulernal. or mucoyM mem* 
braue. Formerly, tlie guta were subjected to the 
putrid formentalion, in order to separate the pen- 
toncal and mucous membranes from the muscular 
one; and this process was accompanied with such 
a foclid cflluvium, that the auihoritiea obliged tho 
manufacturers to establish their works at a dii. 
tance from all other habitations. In 1820, the 
Prefect of Police, of Paiis. proposed to the Sonfti 
if Encouragement, to offer a prixe for a jirocess, 
either chemical ot mechanical, of offeclmg this 
ohjKct wilhout submiltiug the guU to the putrid 
fermenlaliou. 

After the guts have been freed from sll Kreaai- 
ncss. by the usual methods, and turned inaide-oil^ 
they are to be put into a tub, capable of cunlaiiiiiig 
as many as are produced from 50 oxen ; atui Iwu 
buckets of a weak alkaline liquor are to be puuiej 
upon tUera. If ihey BJiould not be sufllciently 
wetted, throw over thein another buckei-tnll of 
well or river water ; they are then to bo iroU stirred 
up, and left to steep all nighL At tlic ead sf Ihia 



fim- '"-I- -^--rmismembrniie may be rcmoTed with 
»« .y AS it cuuld be ah«r many days uf 

ptii -ution. 

ibe oiUce operutioDB may be afterwards per* 
fforated in Lbo usual manner. 

When the workman has stripped off that part 
ftf the psritoueAl membrane which surrouads the 
««rtfa, he ukes from *i to 2| feet in lengtli of it, 
•Ml iiiverti It, or tarns it inaide-oul ; he ihcn 
F«Ave« it to dry; whea dry, it resembles a pack- 
thread. In ihH 4tate it is sold to the manufacturer 
of KuM-beater's skin ; who takes the dried mcm- 
bv.> »>.iks thrm in a rery weak solution 

ri ^^'hcn sutHcioutly soaked, su as to 

b.. gvlattouus, hfi places Ihcra on a 

w . k, IP screpo ihcm clean, and cut 

tt< ■ ih A knife. When the pcUirles ore 

wull cluttt:at;d, and eufGciently freed from the 
water, they are exicndod on wooden frames, three 
•T frmr ft^t lung, and filmut ten itichts wide; 
ihnit: are formed uf two n]irii;hla, joined by Iwt) 
CtOK*- pieces ; tlie cru;iS'[)ieri's hiive grooves uf 
tkrVV or four Untrt wide made in Ihrm. 

Ill order In extend the membrane, the workman 
tekrs it in hit hands, and affixes one end ol it, by 
ttaclutinousqnahty, to the top of the frame, taking 
c.'i ' ' .' p.irl of tho inlt'btine which formed 
(5)' i It be pliii'-ed next to the frame ; he 

ih-2.- - -.- L'Ti'ry way, and causes it to adhere 

•u the oiber end of the frame : this clfected, he 

t»k«s another membrane, and applies it upon lliat 

which is already extended, taking care that the 

BiiiscQlar membranes ahoald be in contact with 

-V thet : in this way, they become bo per- 

I'led tuf!ether, as to form one solid body. 

!*.> MiPinbranes soon become dry, except 

luties, which are glued to the cross- 

< Line. When the whole is well dried, 

•:uta the pelliclcfl across at each end 

r. iiifr, and separates them from the 

liried and stretched membrJiucs are 

i to another workman to pive them 

a ration, and to cut them into con- 

i>k finisli the pellicles, the workman 

i«jh band separately, and glues it on a 

framt* to that which we hare bofure 

' ^ a without a groove: ho applies the 

' edces of the frame, and plaueB on it 

a pellicle. When quite dry, it is 

kied orrr with a solnlion of one ounce of ahim, 

cd in two wine-quarts of wutur, nud again 

Inw^<] to dry ; it i« then coated, by means of a 

ifvtni:c, with n concemrnted solution of isinglass 

>*. in which acnd and aromatic sub* 

'•een steeped, such as cloTes, musk, 

>u. &L\ ; these last substances are 

-eels from attacking the pellicle. 

coated with this composition, 

'■!•' 'voikmeii call It, prounde</, they, lastly, 

:( with a layer of whites of e-gga. The 

LB then cut into pieces of about fhe inchoa 

; sabmitted to the action of a pres.% to 

them ; and then formed into small packets 

books foe sals to the gold-beaters. 




DRYING SEA WEEDS, 

ST 1. 1. DKIMUOND, M, S. 

«f tk» kelful Hitorsl History Socitt)' 

Tv> flcvt object to be attended to in proserring 
■trifia plajiis is t/> have them washed perfectly 



clean before spreading. There should not bo left 
upon them a particle uf sand ur other foreign body, 
unless in some rare instances a parasitic species 
may be thought wurtliy of keeping, on account of 
its rarity, or becanse it may add an additional 
beauty to the chief specimen, it is a good practice 
to wash them befurc learmg the shore either in 
the ica, or in a rouUy pool, or, as is someiimea 
more convenient in soniu localities, in a rivulet 
discharging ileolf into the ocean, Utoneh, as will 
be afterwards explain-d, the Ia.-it practice proTes 
very destructive to tho beauty of some spotues. 

The foreign bodies to be got rid of arc fragments 
of decayed 8ca*weeds, atnd, grarel, and sometimes 
portions of the softened surface of sandstone of 
argillaceous rock on which the specimens may 
have grown, togetlier with the smaller teatacea. 
and the (Jotattinn Q^.inalu, &c. At Caimlough 
Bay I oxpericiiced most trouble in thts respect 
from tho Kciocarpi, which confervic were so geue- 
ralty diffused, as to be entangled with almost every 
other species of sen-plant. 

After the greatest pains which we may lake to 
clean our specimens at the shore, there will genc- 
mlly be found much to do before they can be pro- 
perly committed to paper, since foreign snbstancas 
will continue attached to them with much perti- 
nnciiy eren aftor we may have been aatisticu that 
they are perfectly clean. It is therefore necessary 
to prepare each specimen by examining it in fresn 
or sea water in a white dish or plnte, so that every 
thing foreign may be detecteJ and removed. 

The next thing to be attended to is tho quality 
of tho paper on which the specimens are to be 
spread ; and here a great error is generally com- 
mitted, in using it thin and inferior, by which, if 
the specimen be worth pre8er\ing, it has not proper 
justice done to it. Much of the beunty, indeed, of 
many Bpccit-a depends on the goodness of the 
paper, exactly as a print or drawing will appear 
belter or worse, as ti is executed on psper of a 
good or an inferior kind, Some species, too, con* 
tract so much in drying as to pncker the edges of 
the paper, if it be not aufficienlly thick, for ex- 
ample, DeteMeria taeiniata, and this has a very un- 
sightly appeunmco. That whicU I have from 
experience been led to prefer is thick music-paper. 
It closely resembles that used for druiring, and 
the sheet divides into four Ioavcs, of a moat 
convenient size. 

Whatever pains we may have taken to clean 
the recent specimens, we shall often And, when 
sprcadtiip ihem, that some foreign particles con- 
tinue attached, and for the remoral of tiiue a pair 
uf dissecting forceps, and a camel-hair pencil of 
middle aiso, will be found very convenient. These, 
indeed, are almost indispcnsiblc, and will be found 
useful on more occasions than cau here be speci- 
fied. A silver probe, with a blunt and a sharp 
end, is the moat convenient instrumont for spread- 
ing out, and separating branches from caoh other, 
brit nny thing with a rigid pomt, such as a large 
needle, or the handle of the camel-hair ptsncil 
sharpened, will answer. A large white dinner-dish 
lerres perfectly well fox si)ronding the specimeoa 
in, and all that is further necessary it a quantity of 
drying papers, aud some sheets of blotting-paper, 
with three or four flat pieces of deal board. 
Nothing answers bettor for drying than old news- 
papers, each divided into eight parts, but it is 
necessary to hare a large supply or these. 

The beautiful and common Plocamium eoeei- 
neum is one of the most easily preserved spedas^ 




^MAGAZINE OF SCIENCE. 



* 



I 



And in«^ he taken as itn ex&mplfl of the mods of 
pooMdinr with muct of the oLhera. The lUips to 
DC ptinnrd are na follow*, — 

1. The specimen u to be nerfeelly well clc«Tie<l. 

2. A dluiier'dirth to be tilled about two-tliirls 
with clean fresh water, 

3. The paper on which the specimen is lu bo 
spread, to be immersed in the water in the dish. 

4. The ipecimen to be then placed on the paper, 
and spread oat hj means of the probe and camol- 
hair peocU. 

&■ The ptper with the specimen on it to be then 
slowlj witharawxt from the dish^ sliding it orer its 
edge. 

6. The paper with the specimen adhering to it, 
to be held up b; one corner for a minute or two, 
to drain off the waficr. 

7. To be then laid on a paper, or cluth. upon a 
toble. and the supcrfluoud water stiU remaininfr to 
be removed by repeated pressuru of hloliiuy-paper 
upon the specimen, bediming thi:i operation at the 
edges, inJ gradually encroacIiiaK tuwanik the 
centre Lill the whole can be presaea upon without 
danger of any part adhering lo the blutiing>pAper, 
which probably would be the cose, wurc the latter 
applied at ooco to the whole specimen. 

8. The specimen then to be laid on a couple of 
drying papere placed on the carpet or a table ; two 
men papers to b« laid p?«r it, and then the piece 
of boMd, on which latter a few books are to bo 
pat, to give the neceftMry pressure. 

9. These papers to be changed every half hour 
or oAeoer, till the Apcctiitea is sufiicicully dry, 
(A number of specimens with drying papers inter- 
posed, may be prcased at once under the aaiao 
bosrd.) 

Though the ahoTe method is in general the best, 
yet there are Tariou« species, and among these the 

Plf^" " •-^rcineum itself, which dry perfectly 

*• ' exposure to llic open air without 

pt'- z had recourse to at all; and some 

can oiily tc preserved iu the latter way, being so 

Slutinotia that they wilt adhere as strongly to the 
ryiiig pa{wr laid over them as to that on vhich 
they ATf- spread. Pr«*s»iire. however, is necessary 
aAer iJiry have dried, lur the purpose of flalteaing 
tkem. 

An Lndufpensibtc requisite to the drying of 
marine or frcth water algw it a portion of old rag. 
neither of s fjuality too tine uor too coarse. WUun 
the ■paci m en has Been spread, as ditecti^d, upon 
ilh$t9§»$ <m whkil it IS to remain, a piece of rag 
■HMlrt to cover it ilumtd be laid ovei. and then 
It may be inieitnaved under the boards for prcS' 
■arc. The rag prevocta the iie*^9«ly of so much 



core tB taking np the moi- 
r»qii)res. never adheres l« -. 
dnr* leevaa them, while ui 
fltlvas aUck firmly to the 
have beea sf«cad. 



Dnininiond 

■ -I, bm when 

uii- ^i«tii« theni- 

cn which they 



PROGRESS OP RAfLWAYS. 

Darittglhs past year, (lt^,)11i« fotlowtng lionof 
BeJlwey lievw either been partially opened, or 
epeaed thtmiehoat thmr whole esieut :— > 

The Z^miom amd SnmtAampton Rstlwiv to 
■hirb Ihsoaneof ffeerA WtJttfrm hat been yivta, 
was Qp«n«d on i'ltt** !*», fijhx milr» orwanl, (n 
B<shig«tuk«, At. ... sucj Win- 

chtatat ; Uartt. . n« betwvaa 

IH' nchsster a&^ i'<vt>H^<i'iKv i^r ^umpiaiiaa. 

The Or«at WttUrm Ito* was fluther ep«aed on 
Jdy I. 10 TwWor^, Av» mfla fr«m BotdlDg; tt 



i having been previously opeoed ss Ui 
* Msidenkfad. 

I The Saitem Cwnliti Railwsy is u 
I hare its teimtDi at Webb'c 8<)usr^j 
I Bishopigate*«trect Without sod Shoredi 
LoDilon, and at Great Yarmoulb— ^ dia 
l36mUei: the cngiueer is Mr. Bmilbwaits. 
I this line, 10^ milei, bemeea lh« MiU-«nd 
! and Homford, were opened do June IS. Tl 
I tance ii a series of viaducts and bridges; 
[ being 50 bridges, one of which croeaas the 
I with a span of 70 fe«L 

The iCtanchejter and Leedi Railway was 
I from Maocbrster nnd Littlt^borough. a dii 

16 milrs, on July 3. 
I Of the Y<n-k and S&rtk Midland Raawtr. || 
! miles, (beiwseu York and the junctkov of 
Rnilway with the Leeds sad Se\ttj Une^) 
opened on >iay 30. 

The Midland Ctmntiea Hailaay was 
between Derby aad KoktinghaiD, naaily 16 
I on June -1. 

I Of the Ciatffmr amd Ayr Rnilway, lh« 
between Ayr and Groioe were opened nn Al 
The SinutnffAom oitd '^- ' ' ■ 
' 3^1 miles, was opened i 
; Ihit work bas bf'eo couii 
I at a cost not excfedtug llir e«umat«. 
most im)-ortJinl, •« nprnmjf A dirt><-t r. 
I from the nnrth to I' :^ 

sod Exeter; ibc i 

coinpletinit thr cii. ...CiUg p 

, the last s^ssiou of 1 

The Loudon a„- llailwsy, 1( 

16 yard*, crossed U\ iV bridgei» wie 
lhroiif(hnut on June 1. 

The Ncwcn - ' V ■' <•» '- '• 

miles, ems o[ 
however, \% a ■ 

The BrandHmg Jwitction hailwav is i 
connect thr Tyne and lb*" Wrar, an'! H» i' 
at Cal«**bead with the N'' 
lo complete « railwa* (fi 
Grrnidu 0( t^'an and the L;.^.. o>-. .•••. 
opened on Srrilembcr 5. 

I'ho Ayttfbnty Branch of lh« h\ 
Railway, a straight line, 7| miles lonj|« 
been opened, the junction is made at C 
3& milfs from London. 

C^ Tkt PmkUe ere ra^wvC/W^ 

VM. i. ^ lAte Ma^mnm* i» mm rr«^. 
komtd M etoik mmd irtttrtd, priet S«. M. 

CUik 0>9tr; Ottttrtd), fitr Umdtt^, maf 

k*d t^ tk0 FnlHUktT, pHet lUdL 

CORRESPONDENTB. 

A rawwTAWf KtAoaa^Jl swlsttMi lo hie feMtMi 

numbrr. 
C. C— Wff 1u«a sMrcbad 4llic«wUy. kel «se 

mum (hnn wv h«v« Klrvwtv atatod en " 
J. D. N — W r— rKOTOOSH. •h*lt be 

as poiMhU 
tl. K •^lliMM't root u «<^ to rotor vk««w 
WlU C«rTMp«a4pato obllg* it* hj fetfMof taM* 
M«M Cfleit»b ward or trtt»< : ryffc r i w9 MS 
•mH •*»■ Gtwk iDv«iwe« tfMMcsaaarj irsflMsi 
W ua awas aaawars la nor mmtL 





Aaaki f«v K«vtaw, 

tryOMa, kA, to W -AA I U> Ika 

PrtsMi StrasI 1 lal 
Leosfa mM »• paal pali 



.Pn«l«4ky n ru«vi«,«.WMI*ll«net.aw. Mm 
PabUalw(t.r*i»nt Sanrday W W Bain&ia, It. 
Raw. awl may b« aa4 of all 1 
Tvww aed Catfatry 



»sstoiU»race« 



18 



MAGAZINE OF SCIENCE. 



GEOLOGY. 

POSITION AKO OKNSVAL AmaAKGKMKNT 
or ROCKS. 

At k time wh«n Gcolo^ eog«gr» »o ranch of the 
sttention of the scientific world, and to which it 
will be ftdTtnable occasionally to direct our rwders 
AttentioD t it may be agreeable, and we art wurt it 
will be uaefiil to give a paper, pointing oat the 
general arrangement of the earth'a strata, and the 
natural poaition of ita ro«ka and tDonntaiiis, as in- 
trodoctory to any future remarki, which particular 
circumitancee and disco»eriea may lead ua to. The 
following, thoagh not aiming at acicniifio daiaifica- 
tion, will, we tniat anawer the purpose of com- 
municating a general knowledge of the aubjcct, 
intending at another period to explain each diviaion 
more fully, and alio to notice the organic remaina 
diaeovered in certain of the strata. 

Rocks are gcnermlly divided by geologiaU into 
two grand dtvisioni, distinguiahed by the nantea of 
primary and t^rondary. 

The primary rocks era rompoaed of popa cry*- 
taUiofl matter, and ceruin no rragracuu of other 
rocks. 

The secondary rocka, or atrata, consist only 
partly of crystalline matter ; contain fragments of 
other rocks or strata ; often aboond in the remains 
of vegetables and marina animala ; and sometimes 
contain the remains of land animaU. 

The primary rocks are generally arranged In 
large masses, or in layen Tertical, more or leu 
inclined to the horixon. 

The aecundary rocka are nsaally disposed in 
strata or layers, paralloli or nearly pnrmllrJ to tlte 
bonzon- 

The number of primary rocks which are com- 
bonty obsetTcd iu nature are eight. 

First, ffraniff, is conipoaed of <|unrty, firliUpnr. 
and mica ; when ihe.^c iiodies un* arranged iu rfgu- 
lur layers in the rock, it is called y»«/«. 

Second, mifraeeotm mcAui/um, which is composed of 
quarts and mica arranged in layers, which are usu- 
ally corvilineal. 

Tliird. tienite. which consiflta of the aubitance 
called homhlrndtr and fieldsjHir. 

Fourth, 4rTytrnfi»f, which is roosdtuted by fietd- 
apar and a body uamcd resplendent hornblende ; 
and their separate crystals are often so small aa to 
give the stone a uniform appearance : thia rock 
■bounda in veins of a subftanoe called afratite, or 
90ap roek. 

Fifth, porphyry, which cooaitta of crystals of 
fieldapar, embedded in the same material, but usu- 
ally of a different color. 

Sixth, ffranvlar marble, which consists entirely 
of crystals of carbonata of lime ; and which, when 
ita colur is white, and texture fine, la the aubstance 
uaed by atatuanes. 

Seventh, cfiforife tckitt, whiek eoofiets of oUo- 
rit«, • green or grey substance, aomewbat anologooa 
to mica and fieldspar. 

Eighth, quarttotf rock, which ia compooed of 
quart! in a granular form, aomelimes united to 
amoU quantitirs of the crystalline elementB, which 
have been mentioned aa belonging to the other 
rocks. 

The secondary rocka are more numerous than the 
primary ; hot twelve varietiei iadude all that are 
usually found ia these ialanda. 



First, ^romroele, wbieh conitfta of frvgnunti 
qnorti, or chlorite adiiat, embedded ia ae^Mi^ 
principally compoaed of fieldspar. 

Second, ti/ireewi* tmtdaitme, vhich is compoaadof 
fine quarts or sand, united by a liliaeona cemeot 

Third, linustone. conatfiting of earbonate ofia*^ 
more compart in its texture than in the granahf 
marble ; and often alKvaoding in marine exuvia. 

Koarth. olvminouM tehitt, or *Ao/e, confisttu; <4 
the decomposed materials of diflVrent rocki om 
mented by a amoU quantily of ferrugioou « 
siliceous matter ; and often containing the imprei- 
sions of vegetablea. 

Fifth, calearew* Mmtdgtone, which ia cmlcarooai 
sand, cemented by calcarenns matter. 

Sixth, iron wlone, formed of nearly the «at 
materiais as alumiooas schist, or schale ; but cea- 
taining a much larger quantity of oside of iron. 

Seventh, bvmll or wkrmlone. which coostrti rf 
fieldspar and hornblende, with materials derlfd 
from the decomposition of the primary rocks ; tte 
crystala are geacnlly ao small as to give the rodia 
horaogeneoita appearvooc ; and it is often iMipi— I 
in very regular columns, having aanally five oriiz 
sides. 

Eighth, bittiminamw or e t tm m ^n roe/. 

Ninth, ffypttim, the aabatance ao well knowa b? 
that name, which eooibte of aulpbate of lima ; «a4 
often contains sand. 

Tenth, roc* »tiit. 

Eleventh, chalk, whieh nmolly aboanda in ir* 
mains of marine animala, and eontalna boi iiaital 
layen of Hints. 

Twelfth, piufn-puddiHQ Hone, consiiting of pl^ 
bles cemented by a femsgjnoua or atliceoaa eeaaiit 

To describe more particalarty the eonstitiuat 
porta of the different rwka and atrata will be Ultlr 
understood, unleea the s pecimena could be eiaaiaai 
by the eye ; and a close inapection and oompariaoa 
of the dilTiTent species, will, in a abort time, enabls 
tti^ most common observer to diftinguish them. 

Tlic highest mountains in thaoe iaUnds, and 
indeed in the whole of the old continent, are co«* 
stitutcd by granite ; and this rock has likewise beea 
found at the greatest depths to which the indostry 
of man has aa yet been able to penetrate : micace* 
ous schist is ofien found immediately Hpoo gruite^ 
serpentine or niarhle upon micaceous sehisC ; bvt 
the order in which the primary rocks ore irrounod 
together Is various. Marble and aerpr> 
usually found uppermost ; but granite, i 
aecnis to form the foundation of tiie rocky 
of the globe, is yet sometimes discovered 
micaceoua achiat. 

The secondary rocka arc always incumbent en tho 
primary ; tha lowest of them is usually grauwacke ; 
upon this limestone or sandstone is often found ( 
coal generally occurs between aandstone or shale t 
basalt often exists above sandstone and limeateoe ; 
rock salt almost alwaya occurs aaaociated with nA 
sandstone and gypsnm. Coal, basalt, aandstonor 
otid limestone, are oftea arranged in dUferent aJMr> 
nate layers, of no considerable thickneos, so oa to 
form a great extent of country. In a depth of less 
than 5O0 yards, 80 of these different alternate atraU 
have been counted. 

The veins which a/ford metallic «iibetanc«s, an 
fissures vertical or more or teas inclined, filled with 
a material different from the rock In which thej 
exist. This omterial is almost always crystaUiae ; 
and usually consists of calcareous spar, flour 
quarts, or heavy spar, ettlwr separate or 



strata 
above 




MAGAZINE OF SCIENCE. 



TV) meUUic aulMCaiic«s are genenUj dUpericd 
tkrxigh, or confutedlr luUed with the«« cr7stailine 
biHeii. Tile «eiiu In hard ^raniu tcldom aflbrd 
a«di tudul roeUt ; but tn thr veiai ia toft graaiU, 
mmI in grwua. tin, copper, and lead are found. 
Copper Slid IruQ mre the oaW inctaU utmlly found 
la the vrina in ft«q>entine. Micac«oat schiit, 
MeniCe, uul granular marble, ire seldom meteUifer- 
otu roeka. Lc*d, tin, copper, iron, and tasnj other 
BMtalB, are fonod in the veini in chlorite schJst. 
OraawBcke, when it contain! few fra^nenU, and 
eiitCs in larj^ masnes, is often a metalliferoua rock: 
Tb^ precious metal*, likeivise iron, leid, and anil- 
■ony. are found in it ; and sometimes it containa 
rous, or maaacc of atont coa/, or cual free from 
bitumen. Limestone i*^ the f;TtAt metalliferoos rock 
oi the leoondary famUy ; and lead and copper are 
tha metala moAt UAually found in it. No mctaJlic 
vcfaM have ever been found in shale, chalk, or cal- 
carrooa aandatone ; and they «re very rare in basalt 
■od ailiocotu aandstoae. 

In cases where veins in rocks are exposed to the 
adMoaphcre, indications of the metals tliey contain 
mmj ht often gained from their suptr^cial appear- 
ance. Whcaever flnor spar is found in aveie, there 
is always strong reason to suspect that it is asso- 
«iated with metallic substances. .\ hrowo powder at 
the amrhMof a vein al trays indicates iron, and often 
tia t a pale yellow powder lead ; and a green color 
ia a rein dcnotrs the presence of copper. 

It nay not be improper to give a general de- 
acription of the geological coostituttoo of Great 
Briuio and Irebind. Gninite forms the great ridge 
9i biUa extending from Laud's End throngh Dart- 
moor Into D«Toashire. The highest rocky strata 
in Sonteraetahire are gnnwacke and limestone. 
The Malvern hills are composed of granite, sienite* 
and porphyry. The bighrsl mounlaius in Wales 
arc chlorite schist, or grauwacke. Granite occurs 
at Muuut 5wrrel in Leicestershire. The ^reat 
nagfl of the mountains in Camberland and W'cat- 
Aordaadt are porphyry, chlorite, schist,, and grsu- 
vadte i bat granite is found at their western boun- 
Tkrooghout Scotland the most elevated 
granite, sienite, and micaceous schistus. 
aecondary formstiona are fonnd la South 
west of Dartmoor ; and no basalt south of 
The chalk district extends fVom the 
part of Dorsetshire, to the eastern coast of 
»tk. The coal formations abound in the 
dbtriot between Glamorganshire and Derbyshire ; 
and Ekewise in the secondary strata of Yorkshire, 
Oarbam, Westmorland, and Northumberland. Ser- 
is found only in three places in Great 
i; near Cape Lizard in Cornwall, Portsoy in 
ihire, and in Ayrshire. Black and grey 
marble is found near Padstow in Cornwall ; 
Other colored primary marbles exist in the 
aalgbboarhood of riymouth. Colored primary 
Barbies arc abundant in Scotland ; and white granu- 
rbln I* found in the Islo of Sky. in Assynt, 
the bankA of Loch Shin in Sutherland : the 
coal formations in Scotland are iu Dum- 
i, Ayrshire, Fifushire, and on the banks 
in Sutherland. Secondary limestone 
t^r^f -rp found in mo»t of the low countries 
nVip hills. 

I re are five great assoclatjans of 

uriuius; the mountains of Morne in 

of Down; the mountains of Douegat ; 

or Mayo and Galwa^, those of Wicklow, and 

oi Kerry. The rocks composing the four 





Ant of theae mountain chains are priodpally 
granite, gneiss, sienite, micaceous schist, and por- 
phyry. The mountains of Kerry are cliiefly con- 
stituted by granular quurtx, sod chlorite schist. 
Cohered marble is found near KJIIamey ; and white 
marble on the western coast of Donegal. 

Limestone and sandstone are the common 
secondary rocks found south of Dubliu. In SUgo, 
Roscommon, and Leitrim, limestone, saadstooe, 
ahale, iron-stonr, and bituminous coal are fonnd. 
The secondary hills in these countries are of con* 
siderahle elevation ; and msny uf them have baaaltie 
summits. The northern coast of Ireland is princi- 
pally basalt ; this rock commonly reposes upon a 
white limestonei containing layers of Hint, and the 
same foeails as chalk ; but it is considerably harder 
than that rock. There are tome instances, in 
district, in which columnar basalt is found aboi 
sandstone and shale, alternating with coal, 
stone-coal of Ireland ia principally found in Ki 
kenuy, associated with limestone and grauwacke. 



PROCESS OP THE DAOUBRnEOTYPE, 

It ia pretty generally known that although fha 
French Gorcriimcut have bestowed upon M. 
Daguerre a hamlsomo annuity, for the public uso 
of his extmordiuary iuvenliou, yet ho lias taken 
out a patent to prevent the use of it in this ooun- 
try, not in hia own name but m that of a Mr. 
Berry, in consequence of which it ia furbiilden for 
any one to make specimeus fur sale, or to exhibit 
and instruct othcta in the process whereby the 
operation is conducted ; we are however allowed 
to promulgate the entire and minate procett, and 
tliis wo do in the words of the patent, that our 
country subscribers may know the exaot and 
nulhcntio manner in which Daguerreotype pic- 
tures may be obtained, or made by ihemtelTU. 
The patent says thua : — 

Deacripltoti 0/ tMe Pr-oceat.—Thc reprodoctloa 
of the images received at the focus of the camera 
obscura is effected on plaice or surfaces of silrer 
which may be plated in cupper. The copper serv- 
ing to suppuit the surface or sheet of silver, the 
combLDatiou of these two metals conlnbuting 
towards the perfection of the effect. The silver 
employed ahoald be without alloy, or as pure as 
posalble. l*ho sheet of coppor should be suf- 
Hctently thick lo preserve the perfeit smuothuesa 
and flitnena of the plaLc, so that the imagca may 
not be distorted by tlie warping thtroof, but the 
copper should not be thicker than wlmt would bo, 
required to attain that end on account of tl 
weight of the metal. Tho thickness of the twi 
mcLala united need not to exceed that of a. stoi 
card. The process is divided into Arc uiH'ralionj 
The first consists in polishing and clc.uting ll 
silver surface of the plate, in order to properl] 

firepare or qualify it for receiving the seuBitivt 
ayer or coating upon which the action of the light 
traces the design. The second operation is the 
applying thai sensitive layer or coaling to the sil- 
ver surface. The third in submitting, in the 
camera obacura, the prepared surface or plate to 
the action of the light bo that it may receive the 
im-igea. I'he fourth ui bringing out or making 
appear the image; viciure, or representation . 
which is uut visible wueu the plate is first taken 
out of the camera obscura. The fifth and last 
operation is that of xcmoriog the senaiUro layer 



00 



MAGAZINE OF SCIENCE. 



or CdftUnir, which voiild conlintie lo be aflccied 
Aiit) titutergo (Itficrcfit rhanEus from the action of 
lighi — ibid wotiUl iieco&iarily lend hi dcsiroy the 
tlff«t^n or tnunng *o obtaiued in the c&oia* 
obnciin.. 

Preparing the Surfaot. — For Uua oper&Uon ue 
lequiied. a email phifti of olive oil ; some cotton 
Tery tiiiely carded ; % amall quauLity of pounce or 
pumice powder, ground exlremely fluo» and tie<l 
up in * small bag of mualiu, sumcienlly Uiin in 
texture to allow uie powder lo pass easily tlirotigh 
whan the bag \a ahajcen ; a phial of nitric acid, 
diluted with pure water in about the pro^wrtion 
nf one part of acid to sixteen parts of distilled 
water; a wire ^ino or vtaud on which the plates 
can be placed so as to be heated by means of a 
lamp; lastly, a spirit or other lamp to heat tlic 

filalea. Tbo size of the plat<-s or surfaces aro 
tmilcd by thv dirauusii^n uf the appamlvis — ibc 
plates roust first be well cleaned and polished. 
To effect this, begio by sprinkling the silver sur- 
fHce with pounce, by shaking the bag without 
touchtDg the plate, and then with cotton impreg- 
nated with a little oUve oil, rub it gently on, lightly 
moTiog the hand round in circles from the centre. 
The plates during ihia operation should be placed 
flat on sheets of paper, which must be changed 
when neccaaary. I'he pounce must be sprinkled, 
•ercral limes, and the cotton vhanged several times 
during tlio operation of rubbing. The pcatlc and 
mortar used fur pulTerizing the pounce or pumice 
powder, dhuiild not be formed cither of cast-iron 
or cupper, but made of porphyry. The puuuce 
ahould bo ground afterwards on a glass pluto wiOi 
a ^aas muller, pure water being used m the 
operation. The pounce should be used only when 
pe-rfectly dry. It will bo readily conceived how 
important it is, that the pounce ur pumice powder 
should be sufficiently finely pulverized, so as not 
to cause streaks or scratches on the silver sur&ce, 
for it IS is a great measure upon the fine polish of 
the surface of the plate thai depends the beauty 
of thu imu^c, picture, or tracing produced thereon. 
When the plate is perfoctly polished it must then 
be cleaiit-'d. This is effccled by Justing or sprink- 
ling the powder over the Hurface, and rubbing it 
with dry coltun, ihc movements of ihe hand bcina 
luadL' in circles, and backwards and forwards, ana 
u|i and down, crowsing each movement in order to 
operate fully ou all parts of the sorfaco. This is 
the best mode of nibbing to gain the desired 
r(*fiulu Next a small knot or tuA, is made with 
carded cotton, which is to bo moistened with a 
little ni-id diluted in water as above stated. To 
\io this, the knot <*t cotton may be placed on the 
muuth of the bi>ttlt! containing the diluted acid, 
and pressed tliereon ; the phial being tliou inverted 
and th«.'ii placed again upright, so that the centre 
uf the tiifl of cxiton may be moistened with acid 
without deeply impregnating it; very little acid 
is required, oud caro must bo taken not to wet ttie 
fingers with It. M'iih this tuft so charged with 
Rcid the surface must be nibbed, care being taken 
to carry the acid uniformly over all parts of the 
surface of the plate; the cotton should bo changed 
ecTcral times, and the rubbing of tb« surfaco bo 
made by moving thr hand round and mnnd, and 
crossing as befuro, bo as to extend equally tlie 
acid, which, nevertheless, might to do no more 
than cover slightly the surfaco of tlic plate. It 
will aome(ime<i happen that the acid applied on 
the surface of the plato will be found to accumu- 
late into small glxbnlLti, these must be dMtroyed 
by changing lh(; cotton and by rubbing the plate 



gently* so as to spread evenly iho acid ; for mi A%y 
places where the acid baa been oJiuwcd lu rest * 
lime, or has not be«a hud evenly, it would fom 
spots or stain*. It will be seen that the acid Li 
evenly spcead upon the surlacc of the plate by iU 
appearing covered with a imifurm tint, or what 
may be called a thin veil, or change uf surbcc. 
The plate is finally to be sprinkled with poanco 
or pumice powder, and cleaned by slightly rub- 
bing it with a piece uf carded cotton ; instrnd of 
ordinary pounce calcined Vonotian tripoli ^ 
used. The plate thus prepared id then tu 
mittcd to a considerable degree of heat; to ui' v;u> 
it is placed on a wire frame, the silver surfac* 
being uppermost. Under the plate is to placed a 
lighted lamp which is to be moved about so thai 
the flame shall act equally upon all pexts. Wh<r» 
the plato has been submitted for about five minutrp 
to this uperatiou (ur until Llie heat hu actc4 
equally upon all parts of the plate) it will t*- -^ -- 
cclvcd that the surface of the silver has l 
a whitish lint, or coating, and then the &> i 
the heat mrust ccoso. 

This effect may be obtained by other means ; fiir 
instance, the heat of lighted charcoal may be used, 
which may be preferable, as the opcrali'.>u will be 
sooner flnuhed. In this cose the wire frainf^ t^ im.. 
necessary, for the plate may be laid oo tl. 
or held with tongs, the silver surface a]wa> - 
upwards, and it may bo moved backwards and fuc* 
wards on the furnace, so as to heat it equally 
throughout, until the silver surface beoomei 
covered with a whitish tint as above stated. TIm 
plate is next to be cooled rapidly, by placing it oa 
a cold body ot substance, such as a marble alab, 
or sloiio or metal surface; when cooled, it roust be 
polished again. This may be be quickly done 
tfince it is only necessary tu remove the white tint» 
which Iiiie been formed on the silver surface. To 
ettei't this, the plate is to be sprinkled with pumicM 
powder, and rubbed in a dry state with a poftivn 
of cotton ; tliis should be dune on the surnoe eT 
the plate several times, taking care tu cluouge Um 
cottitn oAen. When the silver is well polished it 
is lo be rubbed, as above slated, with acid dt»- 
Bolvcd in water, and sprinkled with a little dry 
pounce powder, and rubbed slightly with a knot 
of cotton. The acid is then to bo laid upon the 
plate, say three dilTerent times, care being taken tu 
sprinkle each time the plato with powder, and to 
rub it drj' aud very lightly with clean cotlun ; car* 
should be taken not to breathe upon the plate, ur 
touch it witli Ihu parts of the cotton lomli-' 'iv 
Uie finders as the perspiration would prodn 
or status, and dampness of the breath or 
saliva would produce the same defects iu thu 
drawings. When the plate is not intended for 
immediate use or operation, the acid may be oaed 
only twice upon its surface after being exposed to 
the heat. The first part of tlie operation may be 
dune at any titue i this will allow of a number of 
plates beuig kept prepared up to the last slight 
operation. It is, however, considered indisppn* 
sable that just before the roomont of usiiiR tlte 
plates in the camera, ur reproducing the dc^ipn, to 
put at least once mure sumc acid on the plate, and 
to rub it lightly with pounce, as before stated. 
Finally, the plate must be cleaned, with cotton, 
from all pounce dost which may be ou the surCico 
or its edges. 

(Tohe eoHtinued.J 



MAGAZINE OF SCIENCE. 



UULINO MACHINES 

• 

An m&de on different principle*, and at v&rioas 
ecRrts. l^c oltl prinriple u a ver^ expemivc one, 
coatiaf apwnnls of i. 100. Fur general puri>osefl 
decent one» may he obtaiiicil for about ;^5 or ctcd 
low. llie ubjccL to bo obiaineil prinripally by 
ruling; machines, i« a aucct^ftsinn of 9l^ni^Ilt lines, 
for flat tints, asueclionfi in marliim-ry. ^kiea. bnck- 
poiinila, Slc. Ill views aomciiinrs a Itat 8ky tint, 
M mle<1 in. and the shaped uf clouds worked out 
Qp«<rf iT. 119 miiy be »ern on a clnse inipertioii. In 
or Uire a flat tint it U eHwntial that the 

K: 1 'lent of their brin^ prrfrclly pnmlLel 

tu > .».» i'vti-,t. ihuuld nlao be of exactly tho saino 
•p*cc apart; otherwisu a streaky appr>aranc« is 
prodaced. To effect thii> as woU as to prttduco a 
parallality C'f Une (tliough in reality Unc9 arc not 
]iaT«Uel which do not presono au equality of dts- 
from one another) ; a box is made to sUdo 
a bar, a motiuu is then produced by tumiug 
a ijpven distance, the box to Trhich is at- 
tAcbod a diainund or cutting potiiL being drawn 
■long the bar a lino is made upon Lbo surface in- 
tsadtff! to b« marked, and the Dux moTed back to 
in oripnat position ; the screw being tuntcd again 
ttrrcurly the s^Lmi^ distance a uioliun correspond- 
tng to the prcTiouB one is produced ; tho box again 
tffmTrvai.'S the bar, and the cutting point traces a 
•econd Uim by Uio sido of the first. Thifi is tho 
Ct^ttrmtti prinriple of ruling ninchiue«, the difference 
b. in some the bar is made to more 

tt' ' marked upon remaining ttntiunary, 

■wU:ir lu wuicm iHc bat is a fixture, and tUe motion 
to gircn to ihc material ruled. 




Fiff. 1. 




Fig. 1 illustrate* the old-fashioned machine. 

A is the bed, nr moving board, upon which the 

b»j« alidca. C is the sliding box ; to this box the 

maririnp point ifl allatbed, but. as when the line 

I I'VlliepMint it would be impracticable 

-lidiriK box back if tho point were 

"•^■"'l tn ft tint which works on ii cea- 

f 'p sliding bux, so that when tlio 

i it iho terminus of tho line, it is 



raised up, and tlie box then slides back to oom- 
mencG a fresh line. U is the circular nut in the 
aide of the sliding box, working on its ccnlre. E 
is the marking point screwed tu the circular nut. 
F is the screw by which the unifurm motion b 
given to the bed uf the tnac'.ine ; the widlti of line 
varying with the rcvohition uf the anew, n half 
revolution of the screw prpdncing a ncarwr tint of 
Unci than a whole ; a i^tmru-r ihaii n lialf. and so 
on. The width is dcicnnined by u scaW- marked 
upon the screw. 

The following is a more aimplc and loss cxpen- 
sive priuciple than tho preceding. 




riff. 3. 



iHiixi yH:\ipy% r^nwiji riw\ 



•7 



This machioo (fig. 2), consists merely of two 
parallel bars, moving and slopping alternately. 
The width of line is regulnled by a screw placed 
at each end. instead of placuiR the plate to Iw 
ruled upon the mauhino ah in lbo tirst instance, 
the parellel rules are in this case placed upon the 
plato. 'Ihc rulcA are ncrcwt^d to tlie required 
width, placed upgu tho plate, aud tlio bux wHh 
tho ruling point is drawn along along tho upper 
bar. The lower bar is then to be pushed close to 
the upper, and that iu its turn is puiihed forward, 
tho screw rciTulaiing the distance uf movement, 
and preserving a perfect cqualuy in the width ; a 
second liuc is ruled, and su uii throughout, the aamo 
order of movement being observed. 

AA represents the parellel bars. B the eliding 
box with the nut, similar to thai in Hg. 1 CC are 
the screws lil each eud by which the width of line 
is reg\iUtcd. 

The upper figure has the bars extended to the 
width they are screwed to, and in the lower they 
are conlractcd previous tu Ihelr exteus'ton again. 
The bars when used must, of course, be made to 
Nirikc home each wav, ur the liues willnot be equi- 
distant. These machines arc varied in sixo and 
slmpc, according to taste or convenience, as also 
is thf) way tho screws arc placed, the method of 
ABcertniniug tbe disL&ncenf lines. Ac. With more 
complicated machinery greater accuracy is ac* 
quired as well as greater neatness obtained. I 
hftTc seen a machine tint ruled so exceedingly 
neat, that even on a very close inspection, no lines 
could be observed, the tint appearing when printed 
precisely like a wash with Indian ink There can 
scarcely be anything more simple for ruling than 
the la.it-niciitiuiu'(l machine, find for general pur- 
poses ii might be made sufflclontly accurate. I 
need lutnlly adtl that when used the parellel bars 
sh«jnld be prvi*Hcd flrmly down on the substance 
to be rulc'l. aa the least lilting at either end of the 
bar* would throw them out of horixuutal in ruling. 
Thenc machinal are for straight lines only, but tho 
fln«t with a little more contrivance can be made to 
rule linos in relief to represf^nt the undulating sur- 
aces of coins, medals, bos reliefs, &c. 

CHAPtfUB. 



MAGAZINE OF SCIENCE. 



» 



I 



KOYPTIAN BLUE. 

T»i« color, which in »ery brilliitnt, is fmiucntW 
found on the walls of tlir irmpleH in Rfrypt, ind 
&Uo on the ea»es inrltisln^ the niitinmlev The 
lune t*<iIor \% fimn<l in the ruinv of Miine nncicnl 
rdiBcvi in Italy, and cren aoroc of It has been ditt- 
corerrd in thr ntatc It wa« made bv the manurac- 
tnrerf, for the p.iintor« in those rcnitfte tiraeiL 

Count Chaptai analvKrd some at it, fmind in 
IRliO, with H*vfral uilitr n>lor«, tn a fth<i|i ai 
Pnnipeii. He found that it witJt hliio a«hc«, not 
prepared tn the inui!it manner, like ihnt whii-h the 
paper-stainers uw* but bj ralcinntinn. He ron- 
ftidert it a kind of frit, the xenit-rilreoun nature of 
which renders it proof airainitt tlie ariinn of the 
acidi and alkalies at a moderate teiupcrnturv. 

Some ycarslntcr, Sir H. Davyemplnvcfl himself 
In IIaI)' iiy unking rcscarchts tn ascertain the pre. 
panition» of l)ie rolorn used by the Greeks and 
RomaMti and Ih* obtained similar re^ulti ; and 
further bycmplo^inK the synthclic melhoti, be ob- 
tained a colnr Ktmilar to tnat of tlie ancirnts* br 
exiMMinjo; lo a «trnn^ heal, for tWfihounL.a Diiilure 
of fifteen parts carbonate of w^ta. twenty purts of 
jiowclrr»-d Hintn, and ibree part* of copper. He 
thinkft ibii i* the blue de-wribed by Theophnutus. 
who haa aK'hbed the ditu'o* ery oMt (oakiuK of 
Eicypt, and that it wa^ manufae'tured at Alexandria. 

Vllmnuft, who caU« this bloc CfiruUttm^ infortna 
an that the art of makini^ It trim bmoglil by Yea- 
tnrui fn>m F.fiypl to Puzzuoli. and that it was 
made by ealcl'niuR, in a jMUter'* fnrnirr. ball« 
made or land, filinfpi nfropprr. nnd fl<« nilri fear- 
bonate of an<la). The Vem-iiann, -srho were no 
akllfid In rnamellln|{, knew how tn pn*parc the 
Egyptian blue. Neri. in bin treatine DeW Arte 
VftarUt dr»iril>c^ difTi-rvnt I'rtrreei of oxidatloa of 
copper, wbli I) KivrK ihi**- ilifTtirnlroIurii, yi*. r«|. 
gr««o, and blue, and the color Arabicit drito Tmr- 

Although It appears thai this cokw might not to 
bvaiBVlayed tn oil palnling, vet it is much (o be 
arlaliad that we could ret owcr t^e method nf making 
It, «• in di»1cm)>er and dceumiire painting It wotdd 
he of ntcAl ntihty. One muarkabie effect of tblt 
colur ia, that by lam)vhi(ht it appean immewhai 
grccnlali,whiUlbyda) it >hlne« wiib all the briebt- 
iwaa of azure: cidialt ou tlie contra rt, liecomn 
vlolci by artifirlal lighL 

It la thought that Paul Veronese has employed 
tills sort nf blue In many of bis pictures in which 
the skies hare bet-omc green. 'Inr blue ashes, a« 
now iire|»ar*d, would hate caperienccd thi* rhange 
la a lew «cek« ; while the Rgvptian blttr, which 
liaareuiaimilalnKMt w IthiHJt alteration as employeil 
In distemper palutuig, wotild uot for a long time 
lMe«imc affectrd by the actlitn tt( oil. Had Paul 
V a nww aa employed our blue ii%l> M anon 

bftT* dtaoorered their want of ' ' would 

Bol bft?a espoaed his works ag^u .> .•iMt;Arlj la. 
JoritMu chui|{C4. 

la EMttan's JamrmtU 4m Cktmit, \jo9ptk, 199t, 
Ihn author aaanm ui that he had aurewM»d ia eh- 
taintnx the flnntt blur, by raranM nf ||la«i vnlofvs] 
hy C^pef greao This subkUnrc wa« rrdncrd U* 
pvwder, then miacd «tth nltmte nf jKititm, anil 
Iboa HibauiUBg the muturo in a beat ool straoff 
«MMh to Bolt it{ whon it ham cnoiUaMl iaU- 
mam^ft tkacolor haa bccooM hlac i hat If f^uftna 
bad takea ploM. Um maittf vuoM bavt b«ra 




One thing la surprising ; It is that tlw 
maas does not rontain any mnrr atlali la ■ ftaa 
stats, and is hardly loucfaed bt tha acl4a. 
it is flnrly ground, it praducaa a hiiUiant c«Ji 

blue. 

MR. SMEE'S GALVANIC BaTTKRY. 

Or all the acienoes that of Galvaalam haa of ! 
yean made the most rapid stridea. No soa»a 
diaoovery registered than a aecoad Iboadoi fv^^ 
i« made known — no sooner ia oa« &oC oaecftolairf 
than twenty others arlae to aoppoft it. It ia a r«- 
markable aud Important drcumatooce, that aaaay 9I 
these discoveries should be in stoipUljit^ a^io* 
oreaamg the power of apparatus, that wmaim^ ~~ 
greater opportnoitie* in the banda ti Vm oaaH 
Formerly a galvanic iiattery was a Ma 
an expensive machioe, occupying a Lsijia tffacr ml 
eoating a considerable sum to keep It la its short- 
lived afCion. Now. a far more powerful twi 
may be made in a snuff-box and 
pocket. Tboe remarka are forced 
astonishing platiuam batteriea of Mi 
thechemico-mecbanical baCUcriea ini 
Smee, one of which is described by thatj 
as follows . — 

The influence of diflTerenl eoodicloiia oi 
ia a subject which has escaped aQ 
Now thia is singular, for many must have 
thai ia a circuit, the greatest auonticy oC 0m ia 
given off at the comara, edgea and pobata. 
iiig thi» hint, a piece of ipuify platlaooi, 
as it does of an infinity of points, wat 
eoocaet with amalgaroatnl tine, when a 
action tnaogd, so that but little dmbt oookt ha M^ 
tcrtainod of tta forming a very powerfol hMtavr. 
The fra^le oolnreof thia nkoterial preotodas u hmm 
baing Aoa oaad» ood thwaftii ■ it wm diTosoihaJ 
that aaoOor pim of phtiwui aboohl te «a^ 
witb the finely-divided metal. Thia eapvrloMnl oaa 
attended with a ainilar good result, aod Iha 
of the metal thus coated was found lo W 
To lest tha valaa of thia proeeaa, a piaea of ntei- 
num, thai platintxed, waa plooad ia dttoto oaid la 
ooatact with amalj^amated lioc lod Cha 
gaa evolved in a girrn lime waa aodoaA. 

S(|. iMcbm. C larli*^ 

Plattniied ptatioom 7 saw off ^ ia ooa 
Platinam heated ditto 1 In ooa 

Platinum covered by ut ditto 3 ia tU 

In theaa experuaeati tta eontad waa 
orll alike ; tha oaoM alae bok^ aoed, 
uoc« being the aoma bo t ao m tha 
energy of the metal thaa ps a yai ad « 
iron magnet is very great. A plaea 
caposing thiny-t«o »<|uar« Inchca of 
porta thrre-quartsrs of a ponnd thrmtgh 
thickacaaea of paper, whilat whoa 
w«ctad it sappotted it thraogb id a m 
wluB 00 cart waa tokoB aboot te haloft 
whan lifliplr phn^ad lolo tha Hqold, mUf 
•re Uycrt « iha iaoM paper. 

"Hie cause of this iocmue of pnwtr 
the faeiUty giteu tt> the mtlution of 
the numhrr of points, and not fma mi 
surfacr, aa but little beneAt atleoda ibi a 
ia the aiiric acid batttrieo, b which tha 
is not evolved, bat ahaorbod by th« ioU. 

Having Miwrtalaad that a oalotloa of 
BBOot b« aaad far iaeraoalas ^ po«ar of 
tWir ofdfaMff^ ila|a,it ^ingaM a ■■»■ iif 



MAGAZINE OP SCIENCE. 



S3 



^&t. 



ImportSDce to ■jcertuo whether the pUtinam may 
be prmpitaCed npon other metalj with advanUge; 
uid for thia parpOM it wt» deposited upon earthen- 
ware, palladium, pure silver, copper placed with 
silver, nickel. German silrer, tin, lead, bra?*, cast 
imn, *hr«C Iron, ateel. tine and charcoal. The 
platinised earthenware wa« not fgund to onawer, 
apparently from the quantity of the metal not being 
•udScient to carry the electricity. Pallailium, aiUer, 
d pliited silver answered rquntly well with plati* 
to receive the pn^cipitaied metal, and if there 
any difTereoce, 1 think the silver was rnther the 
t. Hlaled cnjiper answers very well, hut care 
should be taken to vamiah every copper edge, or 
el«r (hnt TTirt^l if. apt to be slightly ditaolred. and 
fJopmit"-*! H^Aiu upon the platinixed silver, which U 
injiuio'in, Slmnid copper, from any cause, get 
upon the silver, it may be dissolved by a little 
muriatic acid, and afterwards by a little Ntrong 
ajnmonia. No other metal or alloy hesldea tbta 
answered for the reception of the platinum, exce|K 
iron, and this was as active as silver for a time, but 
then a local battery was formed between the plati- 
nam and iron — the iron was dissolved and the 
battery destroyed. In some cases this does not take 
place so rspidly as in others. Charcoal answers 
admirably for the reception of the platinam, and is 
improved ib like manner. 

We have now the elemeota for the raantrfaoture of 
■ powerful battery ; for we Have seen that increase 
of power is obtained by taking care thAt the nega- 
tive metal is thoroughly wetted by the fluid, and 
that this is not only accomplished, bat its power 
nMCeiially incre-ased by the numerous points formed 
by the precipitation of iinely-dividcd platinum. 
Whatever metal, alloy, or compound may be found 
ksre»fter to succeed for the rrreption of the plati- 
mwa. or whatever meCAl may be found to answer 
nmirt^ of the finely-divided platinum, still the 
principle by which the advantage is gained will be 
Che aMDC. However, the battery which I now pro- 
po«e U to he made of either copper plated with 
di m , tQvrr. palladium, or platinum. The silver 
can be roIlMl to any thinness, and is therefore not ex- 
pcMlv*. Each piece of metal is to be placed In 
water, 10 which a little dilute anlphuric acid and 
«Atro-inariat« of platinum is to be added. A simple 
~ t is then to be formed by zinc placed in a 

Cahe with dilate acid ; when, after the lapse 
time, the metal will be coated with a fine 
powder of platinum. The trouble of this 
I most trilling ; only requiring a little 
after the arrangeeaent of the apparatus, which 
takas even less than the description. The cost I 
to be 6d. a platf of 4 inches each way, or 32 
inches of surface. This finely-divided plati- 
les not adhere firmly to very smooth metals, 
hatwban they are rough is very la«t(ug, and sticks 
ai tdocdy that it cannot be rubbed off. On this ac- 
tmaU wbeu either liWcr is employed, or cuppo- 
■iBtsil with allver. the surface is to be made rough 
If bmahifig it over with a littlt strong nitric acid. 
vUeh gives it instantly a frosted appearaniM;, and 
ttia. after being washed, is ready for the platinizing 




WtA regard to the arrangement of the metal thai 
Mpared great diversity exists ; it may be arranged 
B the oame way as an ordinary Wollaston's battery 
wtth advantagv ; a battery ttius constructed possess- 
og grt«JU:r power than Professor DanieU's battery -. 
har aaAs, oaataining 48 square Inches in each cell, 
Iccoinpcaetl 7 cubic inches of miied gas per Ave 



minotea, wUlst foor cells, of Professor DanieU'a, Ui 

which Gb BqUR inches of copper were exposed 1h 

each cell, gave ofT only five cubic inches in tfae same 

time. Uowevcr, in my battrry thus arranged, the 

action dropped to 5 cubic inches tn five minutes, but 

it reflumed its power after the contact had beea 

broken for a few seconds. The battery olao poa- 

aesoet great beating powers, raising the temperature 

; of a platintim or atrel wire, I foot long and of a 

I thicknesA similar to that used for ordiniry birdcages, 

! to a heat that could not be borne by the finger. 

A small pot battery of six cells fairly fused into 
' globules 2 inches of iron wire, and the combustioa 
of different metals was extremely brilliant, when the 
i battery wu in combination with a Bai-hoffuer'a ap- 
I parotus. A small piece of silver platiniMd (two 
inches each way), with a fold of zmc, was connected 
with a large temporary horseshoe magnet, when it 
j supported upwards of three hundred weight. Ita 
I magnetic power Is not \ett astonishing, three cells 
j supporting thv keeper of a magnet through forty-five, 
two cells through thirty-two, and one call throogb 
tikcnty thicknesses of paper. An electro-magnetic 
, engine was made to rotate with great velocity, the 
1 combustion of the mercory at the breaking of oon- 
i tact being exceedingly brilliant. 
I A battery of this construction should be in every 
' Laboratory, to be used in moat cases where a battery 
j Is wanted, and the slight labour attending its opera* 
tion is scarcely worth mentioning. I have used one 
* for 48 hoars consecutively withoot the slightest 
' alteration either of the. fluid, or in tho arrangement 
of the metali, and the diminution attending its ope- 
' ration appeared to oriae from de6ciency of acid, for 
\ It was instantly restored by a little strong sulphuric 
, aeid in each cell, ^'here the battery it required to 
I posaesa the same power for a long period, it might 
' be advisable to separate the metals by a porous 
earthenware vessel, or what answer* the purpoao 
equally well, by a thick paper bag. the joinings of 
I which must ht effected by shelUlac diasolved in al- 
cohol. By these means, the sulphate of cine is 
retained on the zinc side uf the battery. The osa 
, of porous tubes, however, appears ft^m observation, 
, as far as my battery ie concerned, to be nearly su- 
perfluous, at any rate in most cases ; for I find, 
that after a battery arranged u Wollaston's had 
' been at work in the same fluid for torty*«^ght houra, 
it had no zinc deposited on the silver. It is worth 
I remarking, that during the last 21 hours coutact 
had not been broken for a single Inrianl. Notwith- 
I standing these ex)>erimentfr, however, it may be ta 
I well in an extensive battery to use porous plates, 
I The battery may be arranged like the pot bat- 
' teriea, but I should greatly prefer the trouB;ht, such 
I ai are used for Wollastou's batteries, from the con- 
I veoiencc of packing, and from a battery of the 
I same surfitcc reijuiring so small a space. A battery 
may be constructed to form a most powerful calori- 
I motor. It may also be arranged as a circular disc 
, battery. Or it may be made as a Cruickshanka, 
each cell beinft divided or not by a flat porous 
diaphragm. Whatever arrangement is adopted, the 
closer the zinc is brought to the platinised metal, 
the greater will be th<- power. 

Tlie generating fluid which is to bo employed la 
water, with one-eighth of sulphuric acid tiy mea> 
sure : and the xinc outfht alwayn to be amalgamated 
in the first idstam-r, aii that process will bo found 
very <ECOoomical from its stopping all local action, 
and the amalgamatiou will be found not to requirfl 
repeating, because there is no Cear of copper Ijeing 



10f3CCK 



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cavk nuiY bf* oIIm 

j9m wK. ' The ati 




■■** o«r 4mFt to rofe 
sot rip. T 

»«*• u wi 

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«■&( aAl HMB MAck. ao.l pntir tti 

Tb- 

II intiin 

•«?•«», if *ft t4«r W W«dW. like >ri 













>• fttlMU«t> 
'« fif lk» r\ . 











THE 



GAZINE OF SCIENCE, 

^ni ^tbool of ^m* 



.Vl.J 



SATURDAY. APRIL 25, 1840. [Prick \y. 



Fiff. 3. 




r^ff, 2. 




APPARiVTUS FOR THE DAGUERREOITPE. 



96 



MAQAZIKE OF SCIFKCE. 



PROCESS OF THE PAGUEUREClTVPE. 

(Tle**tmed from paye 10, anti concluJ^.J 

Coating the kur/aee, — For this optmiUun are rc- 
qutrvtt llic fuUuwiii^ i)nplcmcnt5 : * box, as repre- 
senttd in figure 1, and a phial of iodiae. 




yiP' 1. 

Some iodine is to be put into a cnp dish and 
placed in the bottom of the boi. It is uecea»iiry to 
divide the iodtiio into pieces, in ordtT to rrndcr the 
exhalation more extensively ami equally diffutwd ; 
otberwiae on the middle of the pUtc would be 
fonned drclct, or a kind of iri». or appearance of 
a rainbow in prismatic colors, which would prevent 
the plntc from rcneiving n viniforra impression. A 
thin bonrd with ttic pUtc fa^ttned to it is then 
placed with the silver surface andermost, upon small 
brackets or supports, nt the foar angles of the boi. 
ita cover is then closed. In this position the plate 
must be left, until the surface of the sitver be 
covered with a fine gold ting^, which is caused by 
the evaporation of the iodine, condensing U{>on the 
fOrface of the silver. If thu plate were allowed to 
remain too lon^, this golden yellow color would turn 
a porpte or violet color, which must be avoided, be- 
cause in this stRle the costing is not so sensitive to 
the effect of light. On the contrary, if this coat- 
ing is too pale or not sufficiently yellow, the image 
taken from nature would be very deficiently or 
faintly reproduced, therefore a coating of a golden 
yellow is particularly desired, because it is the most 
favorable to the production of the effect. The 
time necessary for this operation cannot be stated, 
because it depends on several circumstances, one is 
the temperature of the room whsitdo the operation 
is conducted, and another the state of the appora- 
tus : for this process should be left to itself, and not 
he alfected by the addition of any other beat than 
that of the room. 

It is very ini)mrlant in tiiis operation tliat the 
temperature iuside the box be equal to that outside ; 
if such wrre not ttic cose, on the plate l>cing passed 
from a cold to a warm atmosphere, moisture wonld 
settle upon itj turface, which would do great injury 
to the effect. Tliis operstion should be leftenCirrly 
to the S})OntAueous evii)Kiraiion of the iodine. 

When the surface O! the plate has sttained the 
proper color, the board ^t ith the ptntr- must he in- 
troduced into a frame whirh is adapted to thr 
ramem nbscora. In this; transference, core mnat be 



bkkeo to pntrent the light striking on the surface of 

I the plat*, asd for this purpose the camera ofaKun 

mav be lighted with a was ttpcr, Oie light of whfcA 

haa' maeh Ibm affect «poD the coated surfaM ; mt 

this light ought not to be oUnwrd to strike too long 

I on the plate, as it wiU eUM Barks or *r»^^ "-> tW 

; same, if allowed to ooBttnne a Iouk ' 

I this second operatioa la completed, li. "> 

1 be pained to the third operation^ or UuU U Uie 

camera obacura. Whenever it is posaiblc, tlw oae 

operation should immcdintely follow or succeed Hm 

Other. The longest inttnol bftwecn the two abotld 

ntit exceed an hour, beyond this lime the action rf 

the iodine and silver surface will lose their requiaitt 

photogenic projicrLieA. 

Tltirit Oyerat ton.— The apparatus ncceaaary fbf 
this operation is the camera obacuns, 6gure J, 
adapted and fittw! to receive the prepared platw 
and their boards. This third operation la that in 
wliich, by means of light acting thruugh the lens of 
the camera obscura, nature rtflect* or impresses (to 
use fipimlive Innguago) au image of heraelf of all 
objects pnlighti-ncd by the sun, on the surface df 
the photopraphic or prepared plates. The obje^iti 
(of nhich the image is to be reuined upon the sur- 
face of the plated should be ns much as poanUe 
lighted by the sun, because then the operatioo is 
more eiptditions. It is easy to conceive that this 
operation being protluccd only by the nccnf ^ .vr 
efTect of light, that ll>e action is the mo- 1 

occordihg Bi the objecU are more brilliantly J 

up or illimiinatcd, or in their nature arc iui>f« it*- J 
tensely white or present bright lines or ^aritu^A. I 
After having placed the camera obscu i 1 

or in front of the objects of which it I 

fix or retain the imnge or obtain a ^e^).^ .-^. ..-|^g^|^J 
is essential first to property adjust the f^^^VI^H^^B 
eamera obscnra so thst the objects be. nf^^^^^M 
perfectly clear and distinct, this is easily done V 
moving forward or backward, the frame of n pUte 
of ground glass in the camera, which glass reoeivcs 
the images of the objects from the lens. When tlas 
frame la brought to the proper position, this uo>«* 
able iJart of the camera obscura is fixed, by me«ia 
of screws spplied for that purpose. The groond- 
glass is then removed from the instrument, care 
being taken not to move the camera obscura, and ia 
the place of the ground-glass is substituted the ap- 
poratua carrying the prepared metallic pUtc or 
Borface, which apparatus exactly fits the place of 
the ground glass pbtc on it* frame. During ibo 
time the apparatus vrith the prepared surface ia 
being fastened into the instrument, by tmall bru* 
buttons or other fastcniuga, the camera obscura it 
closed ; the end i« then opened by means of the 
two semicircles ; the ploto is then in a proper |W)«^ 
tion to receive and retain the impressions of Ihv 
images of the objects chosen upon being open«4> 
Nothing more need be done but lu open the aper- 
ture of the camera obpcurn and to consult a watoi 
to reckon the minutes the prepared surface shall be 
under the action of the light. This operation is of 
a very delicate nature and should be carefidly at- 
tended to, because nothing is visible, and it is quite 
impossible to sUte the time neoeeaary for the re- 
production of the image, as it depends entir 1- -'•• 
the intiiisity of light received by or from 
jecij^, the image of which i? intended to I' 
dnced : the time may vary from three to thir^ 
minutes. It is, however, very im)>ortAnt not to 
allow mure timo to pass than what ia necessary for 
the reproduction, because the clear jarts would na 



MAGAZINE OF SCIENCE. 



97 



}em$^ h^ or remain white or dear, thrj w-oald he 
darkenetl Uy the proloniired urtioa of tlie Iii;bC 
•llnwid to itrike upun tbe l.>Uine ou the tu^ftu.'(^ 
H OD tbe ooDtnry the rime nllowcd is not laifiritiat, 
tbea the proof ur Image would be vague and without 
fvopcr detAita. Su|t[>o«inj;; the operator has failed 
ift pas proof, it being imperfect on account of itii 
hating been withdrawn too Roon or Icfi to rumoiu 
too toog. onolber mojr bo hL'gun tuimedintcly. a 
fSnir hii*imf hrfii )>rfiviou»ly |in;j-'iir«l ; the operator 
1^ ' II of obtaining the proper effect, 

tl> la beine* etirrected by the fjrift. 

It aiit! itmeful in urtlLT to octjuire proper 

pi ike Bonie experimenta of tliis kind. 

" ^ .f haviiiij been sohintttcd to the 

lie rci{uired time, I will proceed 



r "th Operaiifm. — T/i9 Mrrcnrial Proceu. — 
TU« ((Iterator must ha»tr'n to »uhmit the surface of 
UlK pUte to the fourth operation, as soon as It is 
withdrawn r,(itii the camera obecura. Not more 
than one h->i>r oi^ht to be allowed to expire between 
Ihr third 'in>l fimrth operation!, and it ii much 
raorr ccrtoin to ohMin u;ood proofs or tmrings of 
oatufv, whvn the fourth operalitm take.'! place im- 
Biciliatelf after the third. For this operation are 
mjuired the following implements : first a phinL 
contsinint; a qaanlily of mercury or quickiiihcr ; 
iecondlr, tiir appamtui nfterwanls to bo descri)>c<l, 
rrprsseutt:d in figure 3. The mercury is poured into 
tbe ctip, situated iu the bottom of the apparatus, 
and in asufficieatqaantily locovcr the ball or globe 
of a fbermonieter, inurrtcd in tiie side of the box ; 
from this tjme no daylight ma»t be admitted, and 
Cbe rooia must be darkened, and tho light of o 
coodle ur ta|K:r only be used, to enable tbe of>erator 
to iiupect the progress of the operation . The board 
on which ia fiA<;d the plate must be withdrawn from 
thr nixxT ,-.,« already mentioned, as adnpted in the 
cr.: ) apporatu.^ preserves it from the coq- 

C»i The thin bosrd with the plate is then 

IftUodttOod in tho grooves or ledgL*ti of tho blackened 
boanl, 8 ftff. 3 ( this block board Is then replaced 
in 1 r apparatus, which mointaioa it st an 

flc ' f')rty-(ivo degrees, tbe prepared metal 

«u«i«LJi^ >^^"S (daced undermost, so that it may be 
noB Chroogb the side glass, C. Tbe cover A, of 
Iho box must be i)ut down gently, to prevent any 
ptftSdea of mercury flying about In consequence of 
tlw oomprrfalon of the air. When tho whule U 
ttiBS prepanrd tbe spirit-lamp is lighted, and placed 
Bttder the aip containing the mercury, nnd allowed 
to roaioiii until tbe thermometer (tho ball of which 
It ioMaeraed in tho quicksilver bath, the tube ox- 
tflnJinr utitsidi* the box) indicates a tem|K;roturB of 
Centigrade, the lamp thf*Ji mnist be 
the thermometer has rapidly risen it 
nse, even when tbe lamp is removed, 
not be allowed to rise otwve seventy- 
QTe aegrc<ci Centigrade. The impressions of the 
bkOfe (rf nature now oeluaLly exists on tho plate, 
btif it jk rti.i visible; it tsonly oftcr sevoml minutes 
•'I 1-iptcd, that faint tracings of tho ob- 

i's '■ appear, as may be readily ascertained 

W uiap«oUuf( the operation, or looking thruugh the 
|1M» iMiftird by the light of a candle or taper, 
• 1 ' ' ' allowed to strike too long on 

I.. r wonld leave murks on tlic same. 

tUu i<b.u^ =»-.-. >. left in the bos, until thu thur- 

feaswter b«a fallen furty-fived^reea, then the plate 
1* to bs taken out, and thti tiperstion i« Anished. 



W^A njttraiton. — Ftriuff the Tracintf, Dfthwa- 
tiun, or Picturr. — The object of the tiftli <tporation 
is to remove from tlie surface of tho platv, the 
ooatiog of iodine, which otherwise on Its being 
oxjiosed too long to the action of light would 
continue to be decomposed, and wonld thereby 
destroy the picture or tracing. For this opcraiioii 
lire required ll»e following articles: — tir«t, wutor 
Bitturutcd with acfl-(iiiU, or a weak s/dutiun of 
hvpo-aulphate of pure soda; secondly, the ap- 
paratus represented in tigs. •! and 5, (one being a 
side view of the other) and two tnjughii, as aluiwn in 
fig. (>. Into one of the troughs, the solt water is 
to be poured, unlil it is about on inrb in depth, the 
other trungh is to be ftllcd with pure water ; these 
two liquids nrc warmed or heated in tempcroture, 
though nut to the boiling point, la pUce of the 
solution of salt, may be substituted a solution of 
hypO'Sulphate of pure soda, this latter is even 
preftrnblc because it completely removes the iodine, 
which is not always the case when sea-salt is used, 
eaiiecially if the designs or tracings have been 
obtained some time, and laid aside between tlic 
fourth and fifth operations, Tbe mode of opera- 
tion, however, is the same for the two solntionp; 
although tbe solution of byito-sulphate doea not 
require to l>e warmed, and a less quantity of it is 
required than of the salt uud water, aince it la 
sufficient that the phite should bo covered with the 
same, when laid on the bottom of the trough. The 
phite is first to hu immerseil in the pure water 
contuiiictl in one of the troughs ; It muMt only be 
dippiHl in and drawn out irnmediatcly, it is BufficionC 
that Uie surface of Uie plate be covered witli water, 
and then without allowing It to dry, it is to be 
plunged immediately in itio salt water. If the 
plate is not dipt in pure water before tnnuersing it 
in salt water or In tbe solution of hypo -sulphate, 
these solutions would make marks or spots upon 
the surface of tho plate. To facilitate tho action 
of the salt water or of the hypo-sulphate which 
absurbs the iodine, the plate should be moved 
about in tho liquid. When the yellow color or 
tint of tlie iodine i% entirely removed from the 
yurfaco of tho plate, it is to be removed and carefully 
taken by the edges, so as not to touch or injure 
the drawing, and then dipt immediately in the first 
trough of pure water, llie apparatus shown in 
figs. 1 und 5, is tbnn brought into use ; the-^te muj>t 
all bo ;^>crfectly clean, and a vessel or jug Ailed 
witli distilled water, which shoidd be hot, bat not 
iHjiling. Tlie jilate, on being withdrawn from tho 
trough of water, is to bo pinced Immediately on 
the inclined plane F, tig. 4, and without allowing it 
time there to dry. The operator is then to ponr 
upon the surface bearing the drawing, tho hot 
distilled water beginning nt the top of the plate, 
and pouring the water over it in such manner that 
it shnll How orer the surfaco. and carry away with 
it all the solution of sea-salt or of hypo-sulphate, 
which hns been already considerably weakened by 
the immerbion of the plate in tho first trough. If 
the hypo-sulphate has been used, the distilled 
water to be poured over tho snrfaee, need not be 
BO hot as for tho common salt solution. Not less 
than a quart of hot distilled wsttt is required for 
thus washing the surfooe of a plate measuring 
eight or nine inches long, by six or seven inches 
wide. It sometimcEi will occur that after having 
|)oured warm water ou the surface, some drops ur 
globules of wattr will remain on tho plate ; in this 
case they must be removed before tbey have time 



^ 



MAGAZINE OF SCIENCE. 



Is dry* u thpjr mlicht eontAln some partiolcs of ioA' 
Call ot lufUiw and injare tho dniwiDg, tliey mn 
f«nililv removed by •li%)ngl)' blowing on the plate. 
It wUl |)ti ujideritooU bow important it ii tlut the 
water UMnt for ihix wMJiin^ should be perfectly 
pure, for purl uf it will dry ou the suHacc of the 
pUte. MntwlthiUndiuK tlie rapidity with which It 
ui«y Imvu pnatod over It, and if it contains ex- 
InnvDUi D)ult4)r. then nnmerotu and Indulible »]>ots 
would bo formed ou tho drawing or tracing. In 
order to aKcvrtoin that Uio water is auiced for thia 
«Mhlii|, A drou raay bo let foU on ft bumished 
|iUtc. ami if, when evo|K>n»ted by heat it learcs no 
ttaiii 01 mark bcUimI, it inoy be employed without 
fMr ; dt»tilird wntw i^ nlwayi aufficii-utly pure fur 
tUa operation without tit'.ltif; it. When Lhi< 
WMftldniE t* oomptctrd the picture drawing or tracing 
i* AuUliod, Uir «idy tUinjc now to be done is to 
protctVP the turl'arn from being toocbed, tUo from 
diifit ' f- r, which tAmioh tilw. Tho 

int I . Uic Imogn, or in othor wonb 

by 'i - .. -i-ii'h tiip image* ore rendered 

vltjbht, It jwrtJy decvnipo»id« it adhere* lo tho 
•llvHr, It realtli ilie waohing by tJif< w«ter pourvd 
iipiMt tt, liy (If ndheaion, bui it will not beu- uy 
rMJiblHi ut lottcldiig. To prrvom th<«e dimwingi 
Ihrv iiiuit b« ooraM with gUa*. Mcmnhr tUoced ■ 
liiilf ituiva tlm attHto^ bott lb* vdgM or iL* glua 

Mild I ' ■ ' 

and 

thv vuit. 

1^ l.it*A«x«tfn,>Ua««rtla»lfMkiiioftlMioaiM 
l*«i« *<f «|i)ii«iiM* wb«Mn iIm coailaf of lodlDa b 
\Ak\.- r«MwTbcf«b«niatarior 

tHo < ' t of tha bos t it aema, 

■" ' iM operation to conccn- 

i.tihite. which oondcnsea 
:.' \vMrt of tlic bui. Bc- 
Uiw li lb«> w-iip (or evmtMimtt); iha iodtoc. Under tha 
(nnvr <^>vrr tn tbr thlu buord to which h fiicd the 

tdaiv surface downwards^ liolf way down 

• N ' r ii( Aire or oilier gsnoe, which ia to 

ti' )i' itip cup. In order to equoliie the 



recdva the board carrying tho «Ur«r aur&oe or «. 

Fig. 6. U a plan riuw of one oTthe t»«rte n^ 
of copper, tinned ; two soeh trongha ■rvTMuM. 
one for the talt-water. and one fof the pm^ 

fig. 4 and 6, li a repreacnution of the waihi^ 
apparanu, made of tin Tamiihod. To waahS 
dcaigoa on the platca they ar« plaisad on the ftaai 
or angukr ledge, D. E. ia » Jedg, to eoodortSe 
water to tho r«eept«da. C. ^^ 



pl«ii4 aainurad by M»M pav«r or olbcr moain, 
ih»r am ihan lUMlNAbla tnn by tbe Ugbt of 



METHOD OF PRESERVIXn MOSSK3. 
Haviwo often admired the beauiy luid eleoaoocrf 
some of our moaactf, and rogretinB tlmt I ^•'^- ' 
no raothod by which ihay could when enf ' 
preaerTcd, so a« to retain ivny coosidcrabi. 
m their natural appearance I was induJvd, la 
order tu cirecl this desirable object, to moJuf uiai 
of the fulloiniig aimpU, plan, which has succecdad 
beyond expectation. 

Tho piece of mosa to ba preaerred ahooi-' «-' 
be cleansed of all dirt and exlraueous d. i 
should then be thoroughly wetted with . 
water, and placed in a preparation jar or Wid* 
mouthed boltio, in which also a little of the wat«f 
ahould be put-a few dropi i^aufficient. the object 
being to prodnco » damp aimtwphcru around Uw 
plant, which u effected by the continual eraporm- 
tion aiid re<onden«iion of the water in the ioj 
thu of coune beti« to aecoxed as lo prevent ihi 
oa^pc of any poxt&oo of tbe water. 

By this proc«as tbe mou will be found to pj^ 
jcrre both ita form and eo'or. 1 hare now tried It 
^r a pcnod nf «x moBlbe and the mcimeia lo- 
nmn nnchangod. •• freah and as green a. the fuA 
rtay they wore gathered. 
A modorato tempexmtiiro te the moet euluble. 

^ uaaasix. 



t !.r evaiwmclon of the iodine. There 
I . .lU.i II ^\.>.>.:i I) lining formed with inclined sides, In 
llifl sbupe of a vtiiurc funnel ; this shape aasiats to 
dlduatt ruually the rnpnurs of iodine, which spread 
ftN tlii'y rise. 

71»* Vamtra 06»eura, — Figure 3, la a vertical 

•wlhja talieii through a camera obacnra. adapted 

^r tJi« |tmoeaa of DAgiicrrcotypc or photogenic 

pjlaJliieatiou. (bmiiJicd with a frarae for carrying 

lh(« pUt4i i»f ground glass, A. Tho distance this 

-U»% plate is to be from the object glass or lens is 

.Itn unnii' au Uie distiinco at wldch the surface In- 

li'iulrd lo recelvt) the image is pbiced. B, la a 

nlrntr forobM-rvin^ U»e eilectof objects and select- 

HM pobits of virw ; this uiirrorecrvca to enable tho 

(priotor to cbooiie tlie ncencry, tho image of which 

-I Ui be reproduced. When the focua is prujierly 

gutted, the thumb-screw. il, ia turned to 6i the 

rtn lu thin position. Tho mirror is ktj»t closed 

\y iriMint of t^o liotilts at F, which take into small 

yiMt At G ; tho frame and ground-glaaa plate is 

tlhdrown, and in its plnce i^i BulwUtutcd the frame 

urylog the prepare.! phte or sn/face. Tlic object 

la«» I* aidirorootic and periwropic. the concave port 

ust be QuUide of tlie camera obficaro, its diameter 

aliout three and a half inches, and its focua about f 

Fig. 3. is a aide view of ij.e njcrcuriid api>aratu« 
IS the cvver. li the bhitk board whh groove* to 



GLAZES FOK THE LATHE. 

TAiti a piece of dry beoch or other wood, from an 
irich to an inch and half m thickneaa. and ronrfVv 
Shape It into a circular form of about 7 or H 
diameter. Chisel a square bole in tho i 
pasa a wooden or iron axle thrx,ugh It. and wcJku 

nmicd down the edge with the gouge, smooth it 
with the chisoU and form il into theahapeof* 
gnndtitono. Next procure a niece of bnff lUihcr 
of tho requiaito breadth and long enough to » 
oxactly round Bruah the rim ove? with ^uc. an^ 

aide towards the wood, and the edges eroeUvm^ 

1^' J'^*-'" «^'"" ^" '^"*-'^^' of Jhe W^r^S 
spnukle emenr powder upon it Let il rt- main two 
or three days till perfectly set. and it will be fit for 

.^™n ""^^ «^vung round the contrarTway l^ 
turning, and a pot of water should be at liani 
dip Uie tools mto when heated. A amaJl a 
atone fixed in the lathe in iho same manner wM 

i'Jrj^*' T'*^ "I*"'"*- " preferred, water mi, bS 
easily made to dnp upon it while revoIyioT^- ' 
a trough cannot be employed as the watcrwi 

be spLshed ubout by the velocity. 

T. XBirncn. 



MAGAZINE OF SCIENCE. 



W 



CHEMICAL ELEMENTS. 

(Uttumed Jrom page 6J 

18. — Hydnjffen inflamed by tht eUetrie 
■Blow a «uap biilililo with hydrogen, and 
most ntinutc spark through it, and it will 
S«tncil. Tlic cloctricol cnunou aud pistol are 
of tht^ experiment. 
t,~~liydfvfftm tRflianeil by a rttl htai.~~ 
• small bottle of hydrogen gax, an iron 
ited to complete redness ; the ^s will thereby 
led at tlie mouth of the bottle. 
,20. — Musical tound* produced. — Inflame 
gns which issue* froiit the bottle where 
touted, through a tobacco pipe fastened In 
ork, and hold over it so that Uie flame may be 
iy iudowd, a tube of glass about 2 feet 
1 inch internal diameter. As the flame 
a ilrong muucal sound will be prodnced, 
['«oconlittg to the *ixe of the column of air 
)tion, or rather according to the size of 
If tlie tnbe bo perforated with hole«, 
k flutCt a lane may be produced. It is neces- 
that Uie flaxoe should be as small as possible . 
etfictft ia prodnced by the saocessioa of expio* 
I and conaeqaeot ribratioiu occasioned by the 
ion of the gaa in the tube. Other flamea 
[that of hydrogen produce tho same booeuI. 
11. — Renderr certain metnla rttd hat. — Ijet 
of hydrogen goa fall upon platinom 
ly divided state, or as it is then called 
fy ptaiinn. The metal 13 almost immediately 
red hot, and in its turn inflamw the hy- 
Tbc same eflect is produced apon palla- 
iridiom/ though less perfectly, and also 
and diver leaf, if previously heated to 
tcmperatare. 

1. — Hydrogen Tindtr Box, or Dobereiner 
Pi^"*n»e peculiar property of hydrogen causing 
gy pbtiiu to become red hoti and then becom- 
ndamed by it, has given rise to one of the 
kphtcal instruments for producing in- 
iffac, and which may be made available 
irposes uf chemical analysts. It ia 
: (SCO figure.) 




funnel -tshaped vessel, Atted by a 
int into the bottle B. The lower end of 
\ hidlow, and which extends to very near 
of B. hftK plnced oiK>n it a cylinder of 
■(tiMfd there by A cork beneath, which fits 
C ia B tube fitted on to a tiecond neck made 
pttle, and is furniithed with a slop cock ami 
the hydrogen when made, upon some 
plalina ountointd in a little cup beneath Un- 
charge this instrument with liydrogen. U 



la nearly filled with water previously mixed with 
one bIzui the quantity of 8utphuric ncid. Tlio zinc 
Is put on the pipe belonging to A, with the curk 
beneotb it, and A pot in its place. Hydrogen will 
now be generated, and a quantity occupy the part 
of B not filled with water [ here acting with a prea- 
sure upon the water the latter is driven up tho tube 
into A, and by this means the zinc is left bare, and 
no more hydrogen is formed. To procure a li^t* 
turn the stopcocit, aiid the hydrogen wtU pass out 
in a rery minute stream upon the pintiuii. this will 
become red hot, and the bydrogen jet br inflamed, m 
matcli or candle may then be lighted by It : as tho 
gas bums, tltc pressure in 1) is removed, tho water 
again sinks, acts upon the zinc, and forms gaa a 
second time, and so on, till the whole is coosamcd. 
This intttrument its sure and quick in its action, and 
la extremely Tahiablc as a blow-pi|>e for chemical 
analysis and particularly for working in gloas. 

The fnlluwing cut exhibits the same apparatus in 
a ditferent and more elegant form, the couatnictiou 
ia the same. 




A represents a moveuble top to o gloas vessel* 
BB (I rod to buhl ttie lump of zinc C. D la • 
cover for the platinum hox F. The jet of hydrogen 
issued from the figures mouth E. UG shows the 
mixeii acid and wnttir driven up in tlie outer vcflscl 
when the inner one is loaded with gns. The amis 
of the tigure move tlie plug of the stop-cork, when 
the arms arc lifted up the cock is opened ; when 
shut down, the communication is closed. 

(To be contiMted.J 



ARTIFICIAL PEARLS. 

Tnia elegant manufacture is of French origin, and 
h still carried on by that ingenious people io m 
superior manner. They are formed of thin glaat 
bubbles, with their interior surfaces covered with a 
peorl-colored substancr, which is tlirown into them 
through a small tube. The substaooes employed 
for this purpose are the silvery scales of fishes, par- 
ticuUrly those of the bleak ; they are pn-pared by 



30 



MAGAZINE OF SCIENCE. 



being veil beaten tn initar; the ullTery tedimenC 
Bczt onder^gocB several ablations, and is then mixed 
with tnuuparent agglutinating matter, and in this 
vtato ii employed for coating the bulbd. The In- 
rcntor waa a bead-maker of the name of Jacqaln. 
who lired about the time of Hmry tlio Fourth. 
This man obierred, that on washing the scales ot 
the bleak fiih. a very beautiful silver-colored pon- 
der wu obtained, and it occurred tu him that by 
introducing thi« subHtanee into thu interior uf finely 
blown gloss beads, slightly tinged with opaline butts, 
a perfect imitation of real pearls might hit made. 
Jacquin experienced connderable difficulty in pre- 
semng this silvery powder, which if not spoedUy 
made u»r of, <|n)ckly brcume putrid, ditfoikiiig an 
intolerable smell, .\ttcinpti were ma«Ie to prcaerre 
it iu spirits, but this was found to have the efleet of 
dcitroying its beautiful lustre. It was at length 
discovered that the volatile alkali possessed the 
power of preserving tlie substance without detri- 
ment to its luftre. 

The Uoman pearls are formed of a very pure 
alabaster, considerable qmurica of wliich exist near 
t*iaa, in Tuscany. Tlic process is as follows : — 
The alabaster is Arst sawn into slices, the thickness 
of the pearls required ; the pearls ore then formed 
with an iustrament wltich bores a small hule in the 
centre at the same time that the reqiured shape it 
obtained. The next thing in the process is their 
immersion in boiling wax to give them a rich yellow 
hue, and afterwards to cover them several times 
with the silvery substance obCsiued ft-om the scales 
of Che bleak. The singular beauty of this orna- 
ment, which perfectly resembles the renl pearl ; the 
varied patterns in which they ore arranged, and 
their extreme cheapness, render them an object 
much sought after ; while their solidity is such that 
they may be daslied to the ground with vloleuco 
without receiving tlie slightest injury ; being thua 
rendered far superior to those of French manufac- 
ture, which are at once more fragile* tad conside- 
rably less imitative. 

CAuiPfe PearU. — That ingenious people, the 
Chinese, in a manner, force the production of the 
article in the animal itself. They collect the mya 
margaritifeni, or EorupL>an pearl muscle, and pierce 
the uutsides of the shells in several parts, without 
completing the perforation throughout. TIic ani- 
mal becoming consdons of the weakness or defici- 
ency of the shell in those particular spots, dcpooita 
over them a great quantity of its calcareous matter, 
and thns forms so many [»early tubercles over tliem. 
The pearls thus obtained are, howeveri said to be 
generally inferior to those naturally produced. 



LANDSCAPE I'AINTING. 

Landscape painting comprehends all objects pro- 
oouted lo our view in a prospect of tho country, 
and is commonly divided into the Aerojeor Aialori- 
col, and the rvrai or pattoral styles; all others 
partake more or less of these. By the heroic stylo 
i« undentoud those scenes which exhibit whatever 
is great, sublime, or extraordinary in nature or in 
art. 

The mral slylo ia a roprcacntation of countrica 
ffttber abandoned to the caprice uf nature than 
colUvated by man. A landscape comprohendB a 
great variety uf parts, such as situatiofu or open' 
ingst awidenta, citr, •kms and ciotida, qffskipa and 
muuntatna, verdure, roct«, Jhtds, Ivrnicn, butld- 
tttffs, waters/ore ^imnda, ptani«^ trtts andjiffura. 



Sitwakmt or OpwingM. — Tb«ee aro the 

prospect of a country and require groat aki 
putting logalhcr- 

Ac&dcnts. — Accidents to painting oh: variool) 
such as An obstructictn of tho sun's light by ih" 
tDlcrposiiiun of clouds, so thai aomo pari: 
prospect shall bo eulightcced, while oUier^ 
sen red. 

The SJtuitnd Ctouds. — In the langoue ofllM 
painter, too sky meaiu the othcsoni nrmamcnl 
abovo us. The sky it of a hloe color •\: 
more to a white as it approaches tho eanh. 
count of tho intervention uf vapors arising betwpcn 
tltc eye and tho horizun. It is to be obsonwl, 
however, that this light being yellowish oc. 
at sunset, those objects partake not ot ' ' 
liglil but of the yellow or rod color, coi 
the yellow light mingling with the bluo s!^! 
it a tint more or less greenish, as tho yell 
tho Kghl is more or less deep. The proi 
doo^ is to be thin and airy both in 5hapc sfltl 
colore their shapes, tliougli of ondlese varit 
ought to bo carcmlly obderved and studied fn 
nulure. In ordec to make Uiem luuk thin 
picture, tho grounds over which tlicy pass m 
'to bo made to unite with Litem, as if Uto cl 
woro transparent, especially toward^ 
Small clnads in a painting seldoni 
effect, and betray a feebleness of m 
artist, excepting when tliey arc su near on< 
another a.^ in a general way to be consider 
forming only one objoct. 

Qffskips and lUoMnlams.— Offskipa hare a nttf 
nfiinity with the sky, by which Ihoir stri '' ' 
faiotoess is dotermlncd, iho otfskiiw an 
when the sky is most loaded, and brighl*- 
it la most clear. In representing tlio di-.: 
muuiitnins, care must be token tu ruund : 
by proper gradations of tints, and to nvtri 
ncsa ill their extremities, which mokes t: 
pear tu slices. 

TVeet. — Beginners will find in practice that the 
chief trouble of landscape, lies in bundling (retf*. 
as they arc tho most diJlicult part of laudscapc, so 
ore they its greatest ornament. 

Painters usually compriso under tho word shtd^, 
any thing whatever which they either dt-sicn or 
paint scparalclv after the life; whether 
heads, lands, draperies, animals, moui:l 
As the landscapo painter need only study hik u •:>- 
jccts as are to be met with iu the country, we 
would recommend to him some order that his 
drawings may be always at hand ; when he wants 
them, he should copy from nature on sc:pAxitte 
papers the dilTcrcnt cffecls of trees in gcnenu, with, 
their trunks, foliage, and colors. He ought also to 

study the elTects uf the sky. in the several '. —^ *■ 

tlio day and seasons of the year. To . 
themselves in thoBc kind of studies, paiui- 
taken several methods. Thero are some ariisu* 
who have designed after nature in the upcn tifldM^ 
and have there quite finished those pan ' " 
they hail chosen, but without adding any 
them; others only draw the outlines oi ^.,...-1.. 
and slif;hlly washed uvor thom colors for the advaa- 
tage of ihcir memory. 

If it be asked which is the most proper lime for 
lliesG studies, the answer is, tliat natutc shoiibi be 
studied at all limes, because she is tn I 
sonted at all Bcaaons, but autumn yields t 
plentiful harveKi for her fine cITecla; ihe immiM -s 
of the boiisuii^llie beauty uf tliti sky, and 
variety of objects arc powerful inducemenla 



MAGAZINE OF SCIENCE. 



[iaiai«r fur improrin^ his gouiusand perfecting 

we CJinnot see or obtorro everything it u 
" 'T TO make uic of tho BtudicH of others. 
-^ »roc younjr men into Orctfcc, to dc- 
iffs OS ho thought wouhl be of service 
id Diailo use of them to as f;oo<i purpose 
tiiDsolf bsd thorn always on tho spot ; for 
il is 80 far from dtacning censure that ho 
tha contrary to be cDminoD'JcO, as an 
that pixintcrs ought to lr»ve no way on* 
tlic4 for impTovint: in their profession. Tho 
ipc paintiT may urcorthnply moke use of 
iwendtB of aU those who have excelled in any 
in onlcr to acquire a good maober ; like tho 
which gather their variety of buney from 
kt flowers. 

(To be eoneiutkd.J 



[ON OF COLORED LIGHT ON THE 
GROWTH AND GERMINATION OF 
PLANTS. 

OT ROBSET HVMT, nSft. 

.ANTK.D in a box some curled cress seed, and so 

bottles of carmine fluid, chromate of 

acetate of copiwr, and the anamouia 

»hate, that nil bnt a Bniall space of the earth 

exposed to Ught which bad permeated three- 

of each of ttiese media. 

days the only apparent difference was 
coDtinaed damp under the green and 
wheri-As it rapidly dried under the red 
The plumula burst the cuticle in tho 
m lights, before any chan^ was evident 
parts. 

days, under the blue fluid there was a 
of as bright a f^cn as any which 
light, and yor mora abumluHt. 
tip was scanty under the green fluid and of 
tcvlthy color. 

le yellow solution but two or three plants 

yet they were less pale than those which 

fu green light. Beneatli the red bottle 

n&fnbrr of plants which grew was also small, 

;h rather more than in the spot the yellow 

Thry too were of an unhealthy color. 

reversed the order of the bottles, fixing 

the place of the blue, end tlie yellow in 

green. After a few dayi' exposure the 

;«s ap|»cars blighted, while n few more 

plants began to show themselves, from 

of the blue rays, in the spot origin- 

to the red. 

Ident trom this that the red and yellow 

lercly retnril germination, but pofitively 

viul principle in the seed. Prolonged 

iTcred, with genial warmth, free air, 

that can indnce growth, foils to 

[ted v(!gctation. 

Tfpeate<l tlm experiment many times. 

fItHiU, hut the results have brcii the 

' . < the above facts strikingly 

-I" covered by the bichro- 

-7 ' 1 ' i. B plnnt. 

ThcM: n;<>ult« irnni \Uc actcniion of tboie who 

*r* -:.-_.-..! ill the -iinljr of vtgetftble economy. 

I> 'lint at a process by whiiJi the pro> 

. iCM oinro redoUntof light than nurs 

sij be bi.^oi^ht in this inlnnd (o their native 



VAHNISHINO. 
(lUiumtd ftom poff* 8.^ 

rifr/>enltrtr Copal yamitM, 

3 oz. of copal, liqueBed, and 
20 01. of oil or esscnco of turpentine. 

Place thematmss containing Che oil in a balneum 
niariiCi and when the water boils add the pulver- 
ized copal jin small doses. Keep stirring the 
mixture, and add no more copal till Uic fumor bo 
incorporated with the oil. If the oil, in conse- 
quence of its particular disposiliun, can lake up 3 
ounces of it, add a little more ; but stop if tho 
liquid becomes nebulous, then leave the vamifih at 
rest. If it be too thick, dilute it with a little warm 
essence, af\er having healed it in the balneum 
niarifp. When cold, filter it through cotton, uid 
preserve it in a clean bottle. 

This Tarnish has a good consistence, and is as 
free from color as the best aJroholic varnish. 
When extended in one stratum ovor ftmooth wood, 
which has undergone no preparaUun, it forms a 
very brillianl glazing, which, in the courso of two 
days, in sammer, acquires aU the solidity that may 
bo required. 

Tho facility which atlenda tho preparation of 
this varnish by the metiiod here indicntcd, will 
admit of its being applied to all colored grounds 
which require solidity, pure whiles alone excepted; 
painted boxes, thercforo, and all small articles, 
colored or not colored, wbenever it is reqninfd to 
make the veins appear in alt ilic richness of their 
tones, call for the application of this vnmiiih, which 
produces the must beautiful effect, and which is 
more darablo than turpentine varnishes composed 
with oilier resinous substances. 

Fai Amber, or Copal Vamiah. 

4 or. of amber or copil of one fusion, 
10 or. of essence of lurpcntino, and 
10 oz. of drving linseed oil. 

Put the whole into u pretty large matrass, and 
expose it to the heat of a balneum maris, or move 
it over the surface of an uncovered chaffing-diah, 
but without llame, and al the distance from it of 
two or three inches. When the sulutinn is coa- 
pli'ted, add still a little copal or amber lo satnrato 
ihe liquid ; then pour ilio whole on a filler prepared 
^vilh cotton, and Icavn it to clarify by rcsl. If tho 
varnish is toUuck, add a little warm essence to 
prevent tho separalion of any of Lho amhor. 

This varnish is colored, but fnr Uts so than 
those composed by the osunl methods. When 
spread over white wood, without any preparation, 
it forms a solid glaxing. and communicates a slight 
tint to the wood. 

If it be required lo charge this varnish with 
more cupnl. or prepared Jiuiber, the liquid must bo 
composed of two pirts of essence for one of oil. 

Compound ^f aide f'oritiak. 
3d oz. of pure alcohol, 
G oz, of puritied mastic, 
3 OS. of gum Boiidarac, 
3 OS. of very clear Venice turpentine,!;] 
•1 ox. of gloss, coarsely pomided. 

Reduce the mastic and sol ' " 'cr; 

mix ihi? powder wivh while ;: the 

finest pniis have been scj)ariii--i, ^_. ... , .*:uur 

siove; put all the ingrcdientg, with aleuhot, into ft 
Hhort'ncckcd luatross. and aduitt to ii a stirV of 
white wood, rounded at tho ijua, and of a length 
proportioned to ihe height of the matrass, that it 



« 



MAGAZINE OF SCIENCE. 



miy berat in moliofi. BipoaD the mAtrui in • 
vaMsl fiUMt with water, mftde at flnt a btUo wans, 
•&<1 wliich must aftenruda ba main tain od in a 
•tale of eboUUloD for one or two houn* The mat- 
laM may be made Cut to a ring of ttraw. 

When the solalion >ccma to be sufficiently ex- 
tended, add the tujpentiBe, which most bo kept 
•0]»antely in a phial or pot, and which moat bo 
ntlted, by Immersing it for a moment in a bft-tneam 
aari«. Tlia matiaat most be still led in the watei 
tar half an hour, at the end of which it is taken 
otf ; and the vamiih is continually atined till it ia 
aomowhat cool. Next day it ia to be drawn off, 
and Altor(>d throoKh cotton. By theae moana it 
will become excecdin^y limpid. 

The addition of glass mtT appear extraordinary, 
but this substance diTidcs ihe parte of tho mixture, 
which has boon made wiih Uio dry Ingrodicnts, 
and it retains the same quality when placed otot 
the iire. It therefore obvintos with success two in- 
couTcnicnccs, which arc exceedingly troublesome 
to tbodc who compose Tarnishes. In tho first 
place, by dividing tho matters, it facilitates tho 
action of the alcohol ; and in the soeond its 
weight, which eurpassca that of resins, prevents 
theae rctsins from adhering to the bottom of tho 
natraaa, and also the colomtion acquired by tho 
ramish when a sand-bath is employed, as is com- 
monly the case. 

Tho application of this famish is suited to 
articles belongiug to the toilette, such as dreasing- 
boxes, cut paper-works, &c. Tho following poa- 
Bcsses ibe same brilliancy and lustre ; but it has 
more solidity, and is exceedingly drying. 

CampAcratid Maatie Vtirmth/or Pami'mg*, 
VI OS. of mastic^ cleaned and washed, 
\h ox. of p\ire turponliue, 

4 oz. of camphor, 

5 oz. of while glass, pounded, and 

SC oz. of cthcrcous csacncc of turpentine. 

Make tho rnmiah according to tho mctliod indi- 
cated for conipuuud mastic Tarnish before de- 
scribed. Th« comphnr is employed in pieces, and 
the lurpcntiiio is Added when tho solntion of tho 
rvsin is completed. But if the vaniish ia to bo 
applied to old luLJntiiips, ur paintings which havo 
bean already varniflbcd, the turpentine may bo 
aapprcsscd, as this ingredient is hero recornmcniled 
onlv in cases of a Qrat application to nctv paintings, 
and Just frcod from whiio of egg vamidh. 

Tho clherous osaonco rect»mmcnflo*l for varnish 
is that distilled slowly, without any inlcrmisdialo 
flubitance. 

Tho question by able roasters, respecting the kind 
ot Thmish proper to be employed fur paintings, 
has never yet been dctemiincil. 

Some arti»t8, nho have paid particular nitentiou 
to this ohjcct, make a mystery of the means they 
empluy to ulilain the desired oirect. Tho real end 
may be accomplished by giving to the varnish, 
destined for painting, pliability and softnca*. with- 
out being too solicitous in regnrd to what may »dd 
lo its consifitcncu or its solidity. The latter quality 
is pnrticulnrly requisite in varuidhes which are to 
be applied to articles mucli exposed to fViclion, 
such as boxL's. furniture, &c. 

To mnkc Painter's Cream, — Painters who hnvo 
long inlervalB between their p^ririds of labour, aro 
accustomed to cover tlic pnits they have piiintcd 
with a preparation which preserves the frcslmcas 
of tho colon, Dud which they can remove when 




they xcmmo tbair wtnk. Thia prepazalioo it i 

foUowa: 

3 en. Teiy daar not oil, 

I OS. mastic in tears. pulTehicd. and 
} oz. aal •amrai, in powder, (acatale of lead.) 
DiMolve the mastic oil over a gentle fire, and pair 
the mixture into a marble mortar, over tbt 
poonded salt of lead ; stir it with a voodaa pcatllk 
and add water in small quantitiaa, tiU Iha niM 
aaaume the appearance and eonatetrnoa of j 
and reftiao Co admit more wmtar. 



CToU 



•) 



MISCELLANIES. 

Ponmty of CoiloH.— Kill a glasa tumbtcf 
pletcW with aome spirit, so that a few more 
would cause it to overflow. This done ypa 
find no difficulty in introdndnf into tho 
fio filled, a iffkoU kam^fvl pf row caikm. 
experiment was auggcsted by the aoddentati 
coTory of aome wet cotton from a boat which] 
been some time sunk in a river in America; 
it was found that alter tho water <v 
from the cotton, the tcsccI which hr* 11 

remained nearly as full as before th 
removed. Spirits answer much bet: 
fur this experiment, from tho rapidity , .^ 
they are absorbed by tho cotton. Severmi ' 
have been started in explanation of thia 
tuch as, that the tUaments of cotton 
vacancies between the globules of ■" . 
by its capillary attractiun, the cottun M.^nrui^ 
tho globules, and caused Uicm to occupy a IcM 
apace. &c. ; but Mr. Trantwinc, who ha-f ii.xi- 
municated tliis experiment to Uie /' 
Journal^ accounts for the effect more sn!i>( 
by supposing the fluid to insinuate ii- 
the filaments of cotton, and thus per 
to occupy no mora ipace than ia uuu w v^u 
actual solidity. 



CORRESPONDENTS. 

RiiLLio SiLvn msy &• bought In maoy BhOfM la SAm 1am. 
ZiMc HoDa moy t>« CAst by any ono, ihui. PUl ■ fardMB Mt 

wiLh wpI ■■nil. make a liolo In llio aawl ivlia a Kitall rum, 

and p<nir nwUed tine into ti 
J— Puaibl* tnvtal monlda. to Join Ibv win to them: lay 1h« 

wira ou tltv hearlh and potir tb« mota.! apoa It, moA tliov 

alio ia* xtiHi. when Ibry wtll uulte. 
Qi'MTioN* o[ gcDsral IrttPrnt aro never aoawmed on tftc 



wni|i^«r. but only lhi>*r tbtngi of IndWldBal 
J. W. G — The puMTcr ttl » micruacop* Unmuurrd l*y a fiavly 
aividi'd uiusa plat» vallad a nucionelcr, throofh or Mf^a 

wlitch \hv t'bjocl i« *vra. 
Tiia varLli \* tifurvr Ibo lunJo mDli!tlhAii in tatmnn, tovlia* 

rays of the buii falli more direct uf'on us dunny tbo wax^ 

■nor moiuhi, iberefHro It 1» buttor al Uialteoaon.— Tlw IHl 

anufit); uur oent r|UCTi»». 
CoRui-AiNrt. — A qunilrant mnkcr will best anntvr bla nut* 

poiM<. — Tbo Lrcti bar iriust bi> 2 incha* Ihlck, S fteC UK hw 
Masimo UAUKm — Tho ImsI loettwil Is that of dtwbt* IMM 



(C^ The pHhHc are rtxpte^fuUy it\f6rmHt, f$m» 
Vol, i, f^ this Magarine ia now ready, boumd im 
cloth and iettpred, price 8*. 

Chth Cotern, O^tfrredJ, /or Idndmg, may nho la 
had q/" Me PuMixher^ price 1 (i J. 



ConnnunlCAllOM. Books for Kovlew. Invvntloiw Ibr 
Iratlon. he . |4i be addrvaMK) to Ui« Kdllor, al &3, 
Preacot Slrrel : to the Printet ; or la Um |*ut>Uafa«r. 
Lell«ni niQBi be post |>ald. 




Printed by ir FnikNii*. 4. WluU' Htm Liiiir. Uile Cad 

Publiabet! wury Saliifitny by W bKttiAlsf. II, Paumnlif 
Kwn , and nmy Iw had oi all UookiaUtn and ^eWHiaa B 

Tuwm and L«ttnlry 



THE 



GAZINE OF SCIENCE, 




DOMESTIC GRKEXHOUSES AND FERNERIES. 



iii in which the lost fev years 
prmtrr climig*' thnn tht* riillUation 
IS, particularly in those situated in 
of rities. .\ very sh(»rt liino b:ick 
iDTiiiatcd geraoitiins iu poLs, and Uto or 
W bfnri[itb( in glAssrii, wern Almost all 
fbe made lo blostiom in confined situn- 
I if the druixeu of the luetropoUs g«r- 
pimrlmrnl irilh a rlove pink, or a cama- 
Irovoa. or a heath, it wns only a brief 
Khe could make Ihcm survive in Ruch a 
fed atniOi»|ihere ; as to flourishing, it was 
I^Hcstion — crery shrub be might procure 
tated, bhtek, and flowirless. The Daisy. 
I He«rr's*eMe all died, evfn the hnrdjr 
I'Dirift, ftiid House-leek. drH^rged on but 
m Biiitoire. Thmt disctmra^tul, the 
icil no lunger In l^ve his nts in urbtt, 
in other things for those derorations 
to bsTe reaped from the bountiful 



hand of nature. Why this general disease 
mortnlity should tnlte place, was rarionsly explained 
by one p:irty. and (hat by far the moat namerDOS it 
wHii tUuuf^'ht to ari»e fruui want of freMh ttir : by 
«'bich term it wa& undiirstood, air such as that of 
the fields, uncontsminated by the breathing of 
animalii, and not de-oxydaled by the burning of 
culinary and manufactunng (ires. But^Bid nnother 
party, plants ought to thrive better in cities hecfinse 
thoy live upon curbonic acid gas, and botli rc^plra* 
tion and coiubusiiou furniah it to them in greater 
abundance, than in the open country. 

This last opinion being theoretically true, the 
question arieeJ, how is it then thai they dwindle 
under such apparently favorable circumstances? 
Upon reflectiiia upon it we trace scvi-rol causes fcr 
lUis elTect. First, ^*'e must consider that a phnt in 
its native place of growth, or cren in a country 
garden, is subjected always to a seasonable and 
natural temperacvra^ not throvo into anwouted 



MAGAZINE OF SCIENCE. 



tigW hy loo much lieat, nor wUberrd by want of 
woirtorv. la thiMC feuons when pUxits grnw mont 
ngorotittr, natnely. spring lod autumn, tL« dvws 
of nii*l)t till the abaorbent reasels, the modcralc- 
heat of day stimoiatea the lao^id system of vege- 
tation. ThfM rc^ar alterationa of warmth and 
moifture can ecATcely be imitated with conTenienn^ 
in tlomrfetic gardcninj^. Here then if one cauae of 
wsnt of vigor. A second is to )>e found in the in- 
fehor and unequal decree of light. In the open 
conntrr a plaut is surrounded by tlte stron^st 
Tight thmughnat the day — in a room, light oomes 
perhapK only throui^h a window and even then 
withmie cleamrM or brillianre ; thus the stems 
become eloogated. the le«vea stckJy and white, the 
flowers pale and scentless, the fruit abortive, al. 
tliough the poor deplomble plant 'ased itj* best 
endearours to escape to a clearer atmosphere, by 
px>wing towardfi the window, and to obtain every 
particle of tight it cnn by turning all its moveable 
pArts in the same direction. 

A third cause of failure, is the conta mi nation of 
the almrMiiihrre in «hich the plants are placed, not 
fri'i. Tice of carbonic acid giiB, that they 

a>u '.ear; nor yetsulpbarousactdgas, as 

souiv iiiiii; cixii, but hecaufie it is loaded with fine 
particles of smoke, and other exhaljitions which 
eo*l Ares always yield in abundance ; this wafted 
through the nir when hot, settles when cold on 
every thing around, plants and all. Hy this means 
the ports of the ic«Tc* Iwcome cloeged up, the 
stonutK upon their surfaces, whioJi are the organs 
of respiration, cvapomtion, and partly of ahiorp- 
lion, become impeded in their in))>ortant fiinctions, 
aud the tap no longer elaborated by the leaves, 
ceosrs lodpposit those secretions upon which %Tge- 
Utble vigor sod heallh, we may say life, depend. 

It mu«l be evident tliat if we could remove tbe»e 
caueieB of decny, we should he enabled to cultivate 
plaiit« Kitb oocceus in ccmfiaed pUced. Our mind« 
would, thereftirc, nalttrnlly consider nref^uhouses as 
the proper shelter. This is partially true, but these 
buildings arc subject to other and gri>at viri^situdcn ; 
for example, the direct rayx of the sun upon their 
glased roofs concentrates tlie heat within, and if 
the windowii are opened^ the moisture evaporates. 
Thus great attention is rt-quiE^ite, not only to ensure 
A proper degree of wnmith, but of moisture also — 
find the contamination of the atmosphere ic anpro- 
rideil for. 

Hrflecting upon Ihe-^e several cirrunistances, Mr. 
Ward, of Well close- sqniire, one of our first bo- 
Unisd, suggested that if plants were placed in air- 
tight cases, every obetacle to their luxuriant growth 
would be removed, fuliginous panicles would be 
excluded, these casei* being placed in an apartment, 
sufficiently equable temperature will be preserved, 
and the moisture, with which they nre at first fur- 
nished evaporating, will roll down the sides of the 
gUss and be again taken up by the roots and passed 
upwards to the foliage; thus & succession takes 
place as in nature, without the least attention being 
necessary ; and, nlthongh this does not remedy the 
want of light, but rather dimitiishes the small quan- 
tity otherwise nhtaiuuble, yet it is only to choose 
such plaotfi as grow naturally in confined situaHons, 
amid obscurity and moisture, and we are then 
enabled to have a flourishing garden, even in the 
narrowest courts of a city. The size of such a 
garden may be that most convenient to us, from the 
extent of on opartment to the confinemeDt of ■ 
fonimiin gla^d bottle. 



togel 



T)m following direclionfl on the • 
ritngement, and management of D<< 
houfrrs, and on thecboiM and proounn^ vi fur'jctu 
for them, will we hope be useful. 

Plants have been grown in a tiimmun i.uari 
bottle, { white giasa,) and are to be mn 
Put the plant first into the bottle, at. 
little, Ko that nothing but a part of tin: r^'OU *\ii^ 
touch the bottum, or if there be room enon^ nnt 
even theae. Then having some of the pfopw 
earth, in a rather dry state, pour it graduaily is » 
05 to surround the rooti, and lie evenly abtiut titeni. 
Next pour in Kuifirient water to saturate the «arfh« 
and this being done, cork up the l»ottle so ai tote 
completely air-tight. Tbe plant will take root ' 
flourish for a long period without any attcoi 
whatever. It should be kept near tlic light. 

Plants may be raised from toed in the same 
ner, putting in the earth ftrsC, water next, and 
teed being sprinkled on the top — antil the md 
gcrminntrA or begins to grow, it must be plaord tt 
a dark sitaadon. 

Glass cases for growing several plants 
may be made ai follow*. — Procure a wooden 
any oooventent length and breadth, and 6 or S 
deep ; have a groove made around the top 
box to hold a glasi shade, either made of 
like those shades which are used to rover 
vases, birds, &c. ; or else made of five 
glass joined by a strip of posted paper, 
brass or wooden frame- work at the e<lgea. 
the proper earth in the wooden box, and the 
or seeds in it, water them well and put on tbe 
cover. Tbe lower edge of thl* it will be 
bered fits in a groove, made larger than thr a 
to that when the latter ia put on, n 
all around it. It may either rrmai:: 
filled with water or potty — rendena|{ tha cats 
thereby air-tight. 

dTttnhouBt*. — Tlie above are adapted to keep 
within an apartment, as for example, witJiinii^ > 
parlor or study window; but it may i'« ™iiii..*.i m 
couAtrnrt n building which shall be • . 
ing a much larger quantity of plants 
constructed exactly like a common greenhouse, b«( 
not capable of being opened, except by means of a 
door or window communicating with an apartniant; 
thus, although not air-tight, it is defended froa 
great and sudden alterations: — not beinf in 
muntcation with the open Kir. 

Greenhouses or Ferneries, oa they are 
from having Ferns mostly growing in them, ^ 
ftom their size capable of much embeUifthmoBL 
Tbe plants may be arranged in pots, as in a common 
greenhouse — or much better, slanting shelves msy 
be made of slate, or stone, and projecting aoiM 
distance from the wall, earth is rammed beUii4 
them. — Besides this are two other method* uaaDr 
combined, the lower part being formed into a kltw 
of ornamental rockwork, the upper part mvrrrd 
with the rough bark of trees, nailed ou, n 
plants stuck in every canty capable of hold i \ 

Tbe cut represents some of these boildiu^s oi a 
large size laid out in rockwork with fountain, he. 
The plants seen growing in it are colled FEa^s, a* 
account of wbichj and method of procuring MMM 
of them, reqnirfte »nil, &c., planting and after- 
management we propose giving la the next or 
following number. 

(To he cantinue^.J 



MAGAZINE OF SCIENCE. 







th 



CHROMIUM AND ITS COMBINATIONS. 

Tui itxily ope of this meUl, which occura id 

nee for Uio purposes of an, in 

-jhrome-ore, commonly cnlled 

, thuujrU it is raOior a compouud 

the Dxideaof chromiiim and iron. The fmclure 

Ihjj oiiueral js uneven; lis histte impcrfcrlly 

Ulllc; iUoolorbclwaen iron-bUck. and hrown- 

bUck, and lis alrvak browo. lis spciific 

ia the purest state, rises to 45 ; but ihc 

rome-ore (buiid iu the market varies from 

4. Accordiiig to Kluiiroth, this ore eoiisisls 

\\<le of fhroraiuui, 43 ; protoxide of irun, 

J aluiniiift, 20-3; and silica, '2 ; but Vaii- 

■-i analysis of auuther specimen gave, 

ivoly. 55-5, ai. 6, and 2. It is fusible 

*' blowpipe; but it ads npun the 

•'die. al'ter haviji^ been exposed to 

r;r jnioky flame. It is entirely soluble 

tn bur«, at a hitrh bluwi)ipe heat, and imparls 

to i( B t'nq.itifnl green color. 

re i« found at the Bare-Hills, near 

:i Miryi.ind; ia the Shetland isles. 

- ..,.i t'etJar; the dcparlmcnl of Var, in 

Kr»ncc, in Binail quantity; iind near Portsoy, in 

IUj isUire ; ua also in Silesi.i and Kjhcmia. 

tSUromate of Po/o«j.— The ehief application of 
;« nreiti to the production of ehromaieuf potash, 
sale the Tarious other prenaraliuns of 
I'd in the arUare obtained. The ure 
-: iJ a fine powder, by being ground 
under ponderous edge- wheels, and sil'ied. 
n mixed with one third or one half its 
of coarsely bruUcd nitre, and exposed to a 
' !^''*S ''"^ several hours, on a rcverbera- 
' it is stirred abmu occasionally. 
uCactories of this country, ilic 
. -..^ve mixture in pol* i^ laid aside, 
se and expensive. 'I'he cjilcincd 
t;od out, and lixivialtMl -with water, 
yellow solution is then evaporated 
!he chromat* of potash falU down in 
-f 1 !>: i!,. which is iil\ed out 
ii '. I fioltom with a large 
viiU ^.ii^.l holes, and thrown 
I : iL I -x. This saline powder may be 
I . il.ir crystals of neutral uhromalo 
;. solution iu water and slow evapora- 
»T be converted into a more beautiful 
the bidiromale of potash, by 
utrated solution with nitrir, 
. or acetir acid, or, indeed, any 
ironger alTmity for the second 
' than the chromic acid does. 
of potaah, by evaporation of the 
, and slow cooling, may be obtained 
1 aquare Ubles, with bevelled edges, 




or ftal fbur-wdcd prisms. They are permanent in 
lb? *!!. 'lie' a metallic an(f bitter taste, and 



of 
13 



-bout one tenth of iheir wci);ht uf 
I' ; but ill one half of their woiglit 
iter. They consist of chromic acid 
' '■; or, in UVj parts, 68 4 + 31-6. This 
»xJl i* u.ajj employed in calico-printing and 

r»rcTO^- )'cfi<m'.— The chrome-yellow of the 
V^ 'th pipmeut of various shades, from 

<^ '"5 ilw pulest canary yellow. It is 

ic uy .i.i^iinK a lunjiid solution of ihu ncufral 
(the oburc granular salt), lo a solution, 
.llv iim„i<l, of HLcUite or niunlc of lead. A 
P*' '% which mual be well washed, and 

c*^ ' ■ '-I out vf the reach of any fculphu- 



retted vapours. A lighter shadu of yellow U 
obtained oy mixing some solution of alum, or 
sulphuric acid, with the chromate, before puuring 
it into the solution of load ; and an orange tint ia 
to be procured by the addition of snbacGlata of 
lead, in any desired proportion. 

Chromie-Ortvn. — The green oxide of chrome has 
come so extensively into use as an enamel color 
for porcelain, that a fuller account of the boat 
modes of manufacturing it must prove aceeptablo 
to many of our readers. 

That oxide, in combination with water, callo4 
iJie hydrate, may bo economically prepared by 
b'dlihj^ chromate of potash, dissolved m water, 
with hiiU" ii3 weight of flowers of sulphur, till th« 
resulting green precipitate ceases to incroaao, 
wliich uiny be easily aiicorlaincd by filtering a 
little of the mixture. The addition of some potash 
accelerates the operation. Thisconalsta iu com- 
bining the sulphur with the oxygen of the chromio 
acid, so OS to form sulphuric acid, which unites 
with the potash of the chromate into sulplmiif of 
potash, while the chruuic oxide bet omes ii hvdrato. 
Au extra quantity of potash facilitates iKo de- 
oxidizcment of the chromic acid by the formalion 
of hyposulphite and sulphtirel of potash, both of 
which have a strong attraction for oxygen. For 
this purpose ihc clear lixivium of the chromate of 
jtotash is sutliciently pure, though il shouJd hold 
some alumina and silira in solution, as it goner^Uy 
does. The hydrate may be freed from panicles 
of sulphur by healing dilute sulphuric acid upon 
it, which diisolvcs it ; aflcr which it may be 
precipitated, iu the slate of a carbonate, by 
carbuuale of potash, not added in excess. 

i'hromt-Hfd. — Liebig and Woblcr have latrly 
contrived n pnxes* f"r producing a subrhroniatu 
of lead of u beautiful vennillion hue. Into snlt- 

fidlrn, brought to fusion iu a crucible «t a gentle 
leat, purechromo-yellow is to bo thrown by small 
portions at a time. A strong ebullition take* 
place at each addition, and the niat^ becomes 
bUck, and continues so while it is hoi. The 
chromo-ytllow is to be »ddcd till little of the 
saltpetre remains undecomposcd, care bL-ing taken 
not tu overheat ihc crucible, lest the color of the 
mixture ahould bcrnme brown. Having allowed 
it to settle for a few minutes, during H'hich the 
dense basic salt falls to the bottom, the fluid port, 
consisting of chromate of potash ntid saliprire, ia 
lo be poured ofT, and it ran be cinpUivyd again in 
preparing chrome-yellow. The niais rcmiuniiic 
in the crucible is to be washed with water, ana 
the cliromc-rcd being separated frcm ihc other 
mutters, it i« to be dried after proper edulcoralion. 
It is essential fur the beauty of" the color, that the 
Haliui- siilulion should not stand loir ' red 

powder, because the color is lhuf^ mo 

of a dull orange hue. The fine crj ^ ^^der 

subsides so quickly to the botium iil\er every 
ebullition, (hat ihe above prccautiou may be oasUy 
nbservcd. 

Chromic Aaid, — Ohromic acid will pmbably 
ore loug become an object of intcrcal to th« calico 
printrr, the futlowing is llie best method of 
preparing it. To H>0 parts of yellow chroinate of 
potash, add 136 of nitrate of bury lea, eoch in 
solulion, A precipitate of the yellow chromate 
of barytes falls, which being washed and dried 
would amount to 130 parts. But while stiU moist 
it is to be dissolved in water by the intervention 
of a little nitric acid, and then decompost^d by the 
addition of the rcquuiilc fjuantity of sulphuric 



36 



MAGAZINE 01 



ENCE. 



AciU, wlicreby tliv barf tea i« sopanted uxd the 
cbronilc acid rcntaia* *s50cUlcd wilL ibe iiilric 
acid, from whicb il c<tii bv freed by cTaponttion to 
dryness. On le-dissotviiig ibe chromic acid 
rcfiduiim in water, tUtcring and eva|Mirmni]g to a 
l>ro}f«r dr^ec. 10 partd of diromic acid may be 
obtdiocd la cys;al«. 

Tliia Hcid mfty at«o be obtained from rhromitti 
of lime, tiinned by mixijig chro-mntc of ptitaeh 
and niuiiaie uf lime ; itasblog Lbc U^solublu 
tbroinalc of limo vLicb prooipitates, and dc- 
compwag il by Lhc equivalent qQ«j)lity of oialic 
acid, or for ordiitary parpo6es eren mlphuric aokd 
may be cntployed. 

Cbromtc acid is obtained in quadraQj^uIar crys- 
tals of a deep red color; il has a very acrid arid 
■tTptio tiute. It reddeus powerfully l-.tinus pnpcr. 
It 11 dclinquescent in the air. ^Vheu healed tu 
redac«8, it emits uiy^eii and passes iotu the 
dculoxjde. When a little of it is fused alooft wiih 
Tilrooas borax, the coiupoaud assumes an omcraid 
gmca color. 

At chromic acid parts with its last dose of 
OXygeu Tcry easily, it is capable in certain styles 
of calico printing; L>f becoming a ralaablc sub- 
■titule for chtorino where this more powerful 
■ubstance would nut from pecoliar circumstRnces 
be »4m iambic. For this ineciiious applicalton, 
tfte arts are indebted to tlut tnily »cientttic 
auni&cturcr. M. Dauii-l Ka'cniln. of Muihfuse.. 
Ho diacorcred that wbeuevcr chromate of potash 
has itj add set frco by its bcinf? mixed v-iih 
tailafic or oxalic acid, or a neutral Tcgetublc 
aabatoucc. {narch or sucKr for example), and a 
nUDCrsl ai-idt a very lively action 19 produced, with 
^tnTfBjrTtrtrn* <>( heat, and of sevonit (;u>es. The 
wall of this dccompiHMttun is ihr active reagent, 
chromic acid, poMCMirg valaable prupcrtios to 
ih« printer. Watery solnttons of chromate of 
pptaNi aad tartaric acid betn^ mixed, an efferres- 
ccnoe fef produced which hiu the power of destroy* 
TefKtible colon. Bat this power lasts no 
Ihan the etfcrresccnce. The mineral acids 
npon lhc chromate of potash only "when 
Vfvrtable coloring matter, gum. starch, or a 
TiVVUblc acid arc present, to determine the dis- 
— Mfti meal of gas. UuHng this cunous change 
CMoobic add ia cTolTcd ; ami when it tak«6 
pUca Id a reiott, there is cundciiscd in the receiver 
a oolortesa liquid, slightly acid, exhaling somewhat 
of the smell of vtocgar, and containing a little 
cmpyreumatic oil. Th^s liqnid heated with the 
nitrates of mercury ox silver reduces these metaU. 
On these principles M. KtEchlin discharged iudigo 
blao by passing the cloth through a solutiun of 
cbromatc of potash, uid printing nitric acid thick- 
fined with gum upon certain spots. U is probablo 
that the employment of chromic acid wuuld 
tupencde the necesaity of having recourse in 
many cases to the more corrosivu chtoiuic. 

drtjme-Biuf, — The following directions have 
been given for the preparation nf a Unt aside of 
chrome. The concentrated alkaline solution of 
chromate of potash Ls to be SAturatcd with weak 
■ulphuhc acid, an'i then to every b lbs. is to be 
added 1 lb. of roniniun liAlt. and liAlf-A-pound ol 
coDccotruted sulphuric acid ; the liquid will now 
acquire a i;recn cnlor. To be certain that the 
yellow colur is lutally destroyed, a small quanuty 
of the liquor is to have potash ndiied (o it, ftud 
filtered ; if (he liquid is still yellow, a fresh portion 
of salt and of sulphuric acid is to be added : the 
fuid is then tu be cvaporaicd to dryness, re- 



diasoWed, and Bllercd ; the oxide of difoeac fil 

final!) to be prrcipititc'l by caustic potaak. U 
^r r, and being wi 



i^Arvmati 



The chnnn i 

bining with . 

without any Tery sensible change in its ronn ani 
apjtearance ; and hence it has been seut into (St 
mitrkei falsified by very considerable qufi: : 
sulp^ale and muriate of jiul^iMli, the pr- 
which hss oficu escaped observation, to ti^t. i.-- *^ 
loas of tlie dyers who use it so exlcnsiTely. llic 
fnllowirg test process has been devised Vy SI. 
Zabcr, of Mulhouse. Add a large « 
tartaric acid to the chromate in questiv: 
will decompose, il, and produce in a few 
a beautiful amethyst colur. The mi\> 
liquor will, if the chromate bo purr, al! . - ^.- 
no precipitate with the niinttcs vi \nii\if* or 
silver; whence the .tbaencc uf the ftul^^huiL-n and 
maiiatea may be inferred. We must, however, 
use dilate solutions of the chromate and Kcid, 
lest biiartrate of potash be preci|>^ 
will take place if lees tlian GU pai' 
employed. Nor must we test the • 
decomposition be complete^ and till t 
rather towards the green than the \ < 
p/trts of tartaric acid should be atldud i 
chr\tmatc to obtain a sure and rapid ii 
nitrate of potash (saltpetre) is th* ' 
ingredient, it may be detected by tl 
burning coals, when deflagration wLi 
green color is a certain mark of the irn 
tion of the chromic acid partially into ihr 
oxide ; which is effected equally by the sni 
acid aud sulphuretted hydrogen. H • 
metallic acid is disoxygcna.ed by ttr- ' - 
has been long knowu. The trata t> 
arc the nitrates of silver and bi 
previously added so much nitric acid to i: 
lion of the sn»pccted chromate, as to prr . 
precipitation uf the chromate of silver or baryta. 
The smallest luIuUcralion by sulphates or mutialaa 
will thus be detected. 



PREPARATION OF SHEEP SKIN RVO^. 

Thh skins with the wool on are thoroughly clcao- 

sed from all iininiritics and foreign innttcr that 

may adhere lu ihem by wasliingin fi 

and by scraping theilMh side in the 

by the knife. The skins are then r 

is termird, by cullini: ufl' uH th»_* ci. 

ragged parts, when they iiro ready i 

the skius are fur thit purpose s: 

fVaraes, and laid upon titssels with : 

of the skin upwards ; ah mfusiun «jt su; 

the proportion of one potmd tu ti gallon of - 

then poured over the shin, and ilie ti 

is well woikcd into the pores uf tJi< 
aid of the knife. When dry, tlie r.'v 
side of the skin, is next placed upward* asd 
thoroughly washed with a strong alkoline soap aM 
wattsr. and afterwards in fair water, by 
means the grease aud filth arc remuved ; w i 
is dry, the skin undergoes a second <-';■" 
tanning with the suuiarh as before uv 
after bring dried, its h^irsh and n^; 
rendered smooth and soA by rubbuig ii o^ 
pumice stone. In order to dyo il of any co- 
fore it is taken off the frame, its face or wooUv in\ 




MAGAZINK OF SCIENCE. 



37 



inlo fl bath ofUie rrqairoti tint, prcparnd 

riUnury manner for dyinR wool ; iho wasli- 

agiiin be repealed to get rid of tht> 

mng matter whicli nJliurt's lo it. The 

IWL dried acd trimmed to the proper 

constUored complete rugs, and «ro ready 



UER HIGH TEMPERATURE OF 
EUROPE. 

DLls Appear to have formed ihc oom- 

; of organic lifo ou the canb. Tbcir 

llie only thing? mi't with lu the oldest 

ited by water, and these belong to 

}8t simple siracture, — ferns, rceda, 

a. 

becomes more and raoro complicated 

r formalions. riniilly, nooi the sur- 

resembles the vegetaiion of the present 

but -with this very remarkable adilitiou, 

in vegetables which flourish only in the 

h nt luge palni-treci, are found, iu a 

, iu all latitudes, and even iu tlic midst 

sen soil of Siberia. 

ancient world, these northern regions 

> potae«sed, during winter, a tetmieraturo 

equal to that which ia experienced at prc- 

paraUels where large palm-trees begin 

I Tobolsk, there was the climato of 

era! 

over fresh proof of this mysterioiu 
an attentire ex&miDation of the di- 
of plants. 

are, at the present day, species of reeds, 

and lyeopodiums, as well in Europe as 

octial regions; but it is only in wanu 

hat they are of great dimension*?. Thus, 

rison of the dimensions of the same plants 

t, Lo compare, in reference to temperature, 

where ihey were pruduced. Place 

1 plants of our coal furmalious, nut 

Kuropeiin plants, but such as abound 

na of South America most cctebmted 

eu of their vegetation, and you will 

er incomparably larger than the Utter. 

'Ujtorat of France, England, Germany, 

dinavia, exhibit, for instance, ferns nearly 

nth branches 3 feet in diameter, 

lerciicc. 

u;, which, at the present time, iu 

rate regions, are creeping plants. 

aboTO the surface ; which, even at 

f, mider the most favorable cirrum- 

do not rise to more than 3 feet, reached in 

in the ancient world, to the htight of 80 

lost be blind, not to see, iu these enor- 
ocniious, a now proof of the high tem- 
formerly poasessed by our country before 
imptioDS of the ocean. 



S1L^T:RING and TINKING. 

rer try Heat. No. 1 . — Dissolve on ounce 

)lwtr in ftf|uii-fortii, and precipitate it with 

•aJt : to which add ( lb. of sal-ammoniac, 

of whif« Titriol, and ^ ox. of corrosive 

— DiflwUe on ounce of pure atlver in aqua, 
itatc iC with common salt, and add, 



anrr washing. 6 ounces of common salt. 3 ounce* 
each of sandiver and white vitriol, and i ounce of 
sublimate. 

These are to be ground into a paste upon a fine 
stone with a muller ; the substance to be silvered 
must be rubbed over with a sufficient quantity of 
the paste, and exposed to a proper di^ee o( heat. 
When the silver runs, it is taken from the fire, and 
dipped into weak spirit of salt to clean it. 

Silrering on Gilt Work^hy Amatyamation. — Sil- 
ver wilt not attach itself to any met^ by amalg:aroa- 
tion, nnlejta it be firxt gilt. The process \9 the same 
as gilding In cobrs, only no actd should be tued. 
To Siher is the Cold JVay. 

No. 1,-2 dr. Urtar, | 

2 dr. common salt, 
i dr. of alum, and 
20 grs. of silver, precipitated from the 
nitrous acid by copper. 
Make them into a paste with afittle water. TIus 
is to be rubbed on the surface uHt silvered with a 
cork, &c. 

No 2. — Dissolve pure silver in aqna-fortts, and 
precipitate the sUrer with common salt ; make this 
precipitate into a paste, by adding a little more salt 
and cream of tartar. It is applied as In the former 
method. 

To Sthrr Copper Ingot*. — The principal difficul- 
ties in plating copper ingots are. to bring the sur- 
faces of the copper and stiver into fusion at the 
same time, and to prevent the copper from scaling; 
for which purposes fluxes are used. 7^e surface of 
the copper on which the stiver is to be fixed must 
be made flat by flling, and should be left rough. 
The silver Is first annealed, and aftervrards pickled 
in weak spirit of salt i it is planished, and then 
scraped on the surface to be fitted on the copper. 
These prepared sarfaces are anointed with a soln- 
tioD of borax, or strewed with flue powdered borax 
itself, and then confined in contact with each other, 
by binding wire. When they are exposed to a tuf- 
ficicnt degree of heal, the flux causes the surfsces 
to fo-ie at the same time, and after they become 
cold, they are found firmly united. 

Copper may likewise be phited by beating it, and 
burnishing leaf-silver upon it ; so may iron and 
brass. This process is called Fbrncr Plativo. 

7b teparate the Siher from Plated Copper,/^ 
This process ia applied to recover the silver from 
the plated metal, which has been rolled doiru for 
buttons, toys. Sic., without destroying any large 
portion of the copper. For this purpose, a men- 
Ktrum i^ composed of 3 pounds of oil of vitriol, 
1 i ounce of nitre, and a pound of water. The 
plated metal is boiled in it, till the silver is dis- 
solved, and then the silver is recovered by throwing' 
common salt into the solutiou. 

7\) Piate iron. — Iron may be plated by three 
different modes. 

1st. By polishing the surface very clean and level 
with a burnisher ; a.ud afterwards by exposing it to 
a blueing heat, a leaf of silver ia properly placed 
and carefully burnished down. This is repeated till 
a Buflicient number of leaves is applied, to give the 
silver a proper body. 

2nd. By the use of a solder ; slips of thin aoLder 
are placed between the iron and silver, with a little 
flnx, and secured together hy bindiug-wire. It is 
then placed in a clear fire, and continued in it tilL 
the solder mpltsi wheu it is taken out, and on 
cooling is found to adhere firmly. 



MAGAZINE OF SCIENCE, 



And 3rdly. Dj tinning the iron fint, and nniUnf 
tlu itWcr by l\u: intcrmetlta of slips of rolled Cui» 
brought into fusion in ■ gentle heat. 

7b tim Copper and Bran. — BoU six poandi of 
ercMD of tftrtar, fotir gallons of water* and eight 
pouDda of grmin tin, or titi thjivingi. After the 
nutcrUis have boUcd a auflicient time, the snbstuice 
to Ue tinned U put tfaereio, and the boiling con- 
linunl, when tlie tin is precipitated in ita metallic 
furra. 

To tin Iron and Copper Kfjwe/*.— iron which ii 
to be tinned, must be previouslj steeped in acid 
inAteriala, such a* nour whey, distiUera' wash, 8cc. ; 
then »cuurrd and dipped in melted tin, having been 
fint rubl>ed oror with a solution of aal-ammoniac. 
The «urfaoe of the tin is prrvented from calcioiog, 
by coTcrlng It with ■ coat of fat. Copper resaels 
raiut be well clcAiised ; and then a sufficieot quan- 
tity uf tin with sal -amuiouiac is put therein, and 
brought into fuHion, and the copper vessel moved 
at>oat, A litti^rckin is &ninetimr8 added. The 
aal-ammoniDc pimenta tUe copper from scaling, and 
eau>r« Lhc tin to be Axed wherever it touches. 
Lately, ilnr has been proposed for lining ressels 
loatnuJ of tin, tu avuld tlii< ill couBequeaccs which 
hftv* b««n ui^iuUjr apprehended. 



KKURAVINU ON ULAH9. 

Tiiu la nn nniuaiti^' and Homctlmvs a useful cx- 
purliiicnt, lui'l Hi invulvinft al»*J a liutc serviceable 
prai^lictil mAniputaliun, is worthy of desoriplioD. 
9uppunc the oujcct bo to cngrtrc a design on ft 
ptccn of tiat plnaa; common crown gtass will be 
fuund the boat for ilit' purpose, and a pFinc of this 
BabstniK'e should bo procured of such dimensions 
that 1 'irclo may he di'scrihcd upon it largo enough 
lo int Indc the intended dra^n-ing. The ^oss Is 
then to be warmed ovor a spirit-lamp, aond-bolh, 
or other convenient sourco of heat, and mbbcd 
with yellow beea-wox ; tins will melt and by using 
such a quantity of it aa will flow readily apon the 
glass when hot, a oniform coat may be applied. If 
vheo cold it prove lo be not tpiile uniform, still if 
every part of the surface to be engraved be per- 
fectly covered, it will suffice. The design is tnen 
to be traced opon the waxed aide with a coarw 
point, cTcry mark being nude to ix-neualo the 
wax. Tho point may be that of « needle, vt a 
piece of wire, or a brad-awl , if made Rat at the 
cud in ooe direction, but romid >'. .tr .ii. r, so a« 
to roicmble a minute round-edv .■ diffi- 

culty will bo found in making i^h tho 

wax, finer or coarser, according to ihc icJalive 
position of iho edge or end of the tool and the line 
which it is describing. If the design be preriously 
drawn upon paper with ink, it may be easily seen 
and tracud tliruugh the wax. 

An evaporating basin, cither of earthenware or 
metal, is to be selected of a diameter that will in* 
elude tlie whole of the design when tlio gltiAS plate 
is inverted over its mouth. Coarsely bruised lluor 

Xr, in quantity equal to about twn ouncra fur a 
t biLsiu, in to be put inio the bafilii with a suffi- 
cient quantity of strong oil of nlriol to moke it 
into a thin paste ; the (wo substances are to be 
stirred tog;ether with a wire, and tho waxed plate 

Sat over the mouth of ilie basin with tlio design 
ownwarda. A moderate beat is then to hi? ap- 
Slied to the holtom of iho basin, which is best 
one by means of the sand-bnlh ; it soon causes 
Uio evolution of fumes in abundauce from the 



" This subttance, which has wry injaduuwttf 
been termed Azcytoyde SaasoA^s, (an Bp|»rIUtfon 
which tends to confo'ind it with the* tsi^r.- 
yielded by the l^nnu Sassafras, of the i 
continent of America) affords so Car as m 
ledge eitends, a solitary instance of a p«rf' 
tile liquid without the aid of art. Substituut,^ ..)r 
tht oppellation to which I have objected the provi. 
sional name uf tlic ' S*iirt> fjii ^f Jjnurtt,' I nhaH 
describe the method of procuring it, aal 
enumerate its principal chemical and mediciiMl 
properties, ns far as these hare beea invotigolal 
and examined. 

'■ The Native Oil is yielded by a tre« of c 
able height ; its wood is aroBiatic, romp i 
texture, and of a brownish color, and tL; .v„:_ 
abound with essential oU. 

" Tliis tree which is Hound in the vasU forests 
that cover the flat and fertile regions between cIk 
Oronuoko nnd the Porime, has, from an analoiry 
already allndcd to, being supposed to ' " 
natural order Laurinea : and thou. 
and Booplaml do not seem to have bt.... ... . 



luUiiue, hut should ne««r be allowed lo 
BO as to melt the wai on any pact of tfas gfauii a 
tcfliporaiurc of iuT or 16Cr is sulBcienL Ths 
basin and its contents, being wanned, obould W 
removed to a cooler port of the saod*balV uj 
left for half au hour. The etching is k 
proceed well when, upon raising one ci. 
plate, vapours are visible within. At ihe via oi 
the hialf boar the glan plate should be rinired wiji 
water to wash off the adhering acid, and die wn 
removed cither by scraping it with the edge of a 
flat case knife, or otherwise. The desini w^l 
generally be found perfectly engraved ' 
gloss, and may be rendered still more c^ _^ 

lightly rubbing over it a Utile finely powacrva 
Vermillion with a ball of cotton. 

If the glass tu be etched or eT>irrA\r(I h«> •> 
formed as not to close the month 
capsule^ it must be waxed all over, 
dont- by dipping it into the melted si 
after the design is drawn opon it, ' 
with the mixture of floor spar and 
into a vessel sufficiently long- and (' 
the whole of the gloss to be "etched. 
of flnor spar and sulphuric acid is to be j 
the bottom, and the glass supported ovir 
corks or wires, or suspended so a« 
contact with the mixture. The tt^ 
be covered over, that the vapour whi. .1 ..s' :> ;<»« 
be retained and surround the glass on every nAis 
ETapornting basins, metallic dishes, ur nilirr 
metallic vessels, not having sufficient dc; 
be mode to answer the purpose by a p«i»- 
cone put ovor the edge raUicr tightly, i 
part of such a cone serves the purp(»»e ol 
W for the reception of the glos^ lu be ei.;:i«,r-„. 
and the rapotirs that arc to act upon it. 



NATIVE OIL OF LAUREL. 

Ax aooount of this extraordinary veg«Ub1e r>ni~ 
dacCioa, a knowledge of which has been 
exclusively confined to the inhabitants of 
Guiana, was drawn up by C. S. Parker, 
Gls^ow, upon a late visit to Demer«m 
gentleman, assisted by Dr. Hancock, a phj»i mu o* 
that colony; from which we make the foUowing 
extracts : — 



I 



MAGAZINE OF SCIENCE. 



liar end important proilucc, ita botani- 

tn maj yery posaibly have been deiieribed 

r Ofmtrti et Sjiecien Plantamm Ame* 

rWonc/tf, tinder the ^cnrrq Ocoten, 

Fative Oil of Laurel is procured by striking 
It Uic proper vessels ia the internal layers 
rk ; while » calnbiuh is held to recciTe the 
rh gruhes oat in such abundance, that 
irtt may be canght from a single incision, 
iKion be performed with dexterity. So 
iwr, are the intliuations of these reser- 
lodianfl (with perhaps a little of their 
uaurt, that a person unacquaio- 
it art may hew down a hundred trees 
dlecting a drop of the preciooa fluid. In 
properties the Native OU resembles the 
oil obtained by expression, distillation, 
arti6cial processes: it is, however, mono 
le and highly rectifieii than any of them, its 
iTitr hardly exceeding that of alcohol, 
it is colorless and transparent ; its taste 
and pungent ; its odour aromatic, and 
lied to that of the oily and resinous juice 
lifera. It is volatile, and evaporates with- 
mm at the ordinary atmospheric tempera- 
ia indamixiable, and, ejicept when mixed 
ihol, giTcfl oot in its combustion a dense 
Neither the acids nor the alkalies seem to 
•enaible action npon the Native Oil : 
led, however, with snlphnric acid, the 
a niomeatary brownish tinge, but soon 
IraQsparency. The Oil of Laarei dissolves 
caoutchouc, wax, and resins; and readily 
with volatile and fixed oild. It is insolu- 
; soluble in alcohol and ether. Though 
gravity of the oil greatly exceeds that 
the compound formed by combining them 
irtion of one part of the former to two 
floats npon the surface of pure ether, 
therefore be the lightest of all known 

respect to the medicinal properties of the 
f, it bears, w4ien externally applied, the 
of a powerful discutient, and appears, 
liblted iniemally, to be diaphoretic, diure- 
id rcsolrant : by many it is believed to be 
I, alterative, and anodyne ; and to promote 
tion of carious bones.*' 
:y has been demonstrated in rheumatism, 
disorders supposed to originate in a 
lof the blood : and the employment of 
has likewise been attended with the 
in paralytic disorders ; also in 
lacbe, sprains, and bruises. " To 
" tiie vegetable physiologist in parti- 
Oil qf //owre/, elaborated by the 
id of nature, in a state of purity which 
processes of art may equal but cannot 
its an interesting subject of inquiry, 
of speculaciou." 



IG WOOD FOR VENEERS, &c. 

wood is mostly applied for Uic pnrposc of 
while staining is mure (teneraily had re- 

to give the desired color to Uiu article 
lu been manufactured. — In the one case, 

should penetrate throughout; while in 
tr* thr vrfftce is all that is essenlial. 



In dyeing; pear-lrec, holly, and beech. Likethe 
beat buck; hut for most colors holly is prefor- 
uble.— It is also best to hsvo your wood as young 
and iis newly cut as possible : After your vruccrs 
are cut, they should be allowed to lie in a Lxougli 
of water for four or five days before yon put Ibem 
into the copper; as the wa(or, acting as a purga- 
tive to the wood, brings out nbundaocu of slimy 
matter ; which, if not thns removed, the wood 
will never be nf a good color ; nflor this puriUca- 
tory procct«8, they should be dried in the open air 
for at least twelve houra : they are llion ready for 
the copper. By these simple means, the color 
will strike much quicker, and be of a brighter hue. 
It would also add to tlie improvement of the colors, 
if, aRcr your veneers have boiled a few hours, 
I hey are taken out, dried in the air, and again 
immersed in the coloring copper. Always dry 
veneeni in the open nir ; fur Are invariably ii^nrcti 
the colors. 

Fine Black. — Put six pounds of chip logwood 
into your copper, with as many veneers as it will 
conveniently hold, without pressing too tiftht ; till 
it with water, nud let it boil »Um>l^ for about tbrco 
hours; then add half a pound of powdered verdi- 
gris, half a pound of comHiros, and four ouuces of 
bruisod nut'galU; fill the copper up with rinegnr 
OS the water evaporates; let it boil genllv two 
hours each day, till the wood is dyod through. 

Ann^ker Method. — Procure some liquor from a 
tanner's pit, or make a strong decoction of oak- 
bark, and to ererr gallon of the liquor odd a 
quarter of a pound of green copperas, and mix 
tiicm well together: put the liquor uito the copper, 
aud make it quite hot, but nut to boll; immerse 
the veneers in it, and let tUero remain for nn hour ; 
take them out, and expose lliem to the air till it 
had penetrated its Bubstanco ; then add some log- 
wood to the solution, place your veneers again in 
it, and let it simmer for two or three hours ; let 
the wliole cool gradually, dry your veneers in tlio 
shade, and they will have acquired a very fine 
black. 

Fine Blue. — Into a clean glass bottle, put one 
pomid uf oil of vitriol, and four ounces of the best 
indigo pounded in a mortar ; (take care to set the 
bottle in a basin or canhcn glazed pan, as it will 
ferment ;) now put your veneers into a copper, or 
stone trough; (ill it rather more than one-third 
with water, and add as much of the viinol and 
indigo (stirring it about) as will makes fine blue, 
which you may know by trying it with a piece of 
white paper or wood ; let tne veneers remain tUl 
the dye has struck through. 

The color will be much improved, if the solnlion 
of indigo in vitriol be kent a few weeks before 
using it ; you will also find the color strike better 
if you boil your veneers in plain woler till com- 
pletely soaked through, and let them remain for n 
few hours to dry partially, previous to immersing 
them in the dye. 

Another. — Throw pieces of quick lime into soft 
water; stir it well ; when settled, strain or pour 
off the clear part, then to every gallon add ten or 
twelve ounces of the best tunjsole ; put the whole 
into your copper with your veneers, which should 
be of white holly, and prepared as usual by boiling 
inwAicr; let them simmer gently till the color 
has snilicienlly penetrated, but be careful tiot to 
let them boil in it, as it would injure the color. 

A Fine Yeftow. — Reduce four pounds of the root 
of barberry, by sawing, to dos^ which put m a 
copper or brass trough; add four ounces of turme- 
ric, and four gallons of water, then pat in as many 



MAGAZINE OF SCIENCE. 




m ike Ufur wfll earn ; %«fi 
fcr 

4y« «fll Mrfkt (bfovch wadi wooer. 

il Mrtfi^ r«aiMr.— To crny |[«Iloin «f vtlcr. 
' U c«v«r yoar Tnren, txld on* pooad of 
boQ the Tcnrm till the color hat 
tkmwk : sdd the followiDg h^pud to 
■ tff l£« French befrics, and lei yout 
tor two or three honn, uid the 
epfll be Very briitht. 
iJfltti/^ Brighttniny and SfUimy Cb^OTV.— 
To rrefy pW of tttotiK aquK-fortii, add one otmcc 
ol^ (TbIh In. okI e piece of eal -ammoniac of ihc 
•ftee e# • wiilsol t Kct H br to diMolve, thaJce the 
%tMh Hmd with tli«f*ork out. froTn time to time : 
im Uhe eovee of tw or three day* it will be fit for 
■ML TMi viU be fonod An Kdniix»ble liqaid to 
!• any color, u it not uuly brigfatertf it, but 
It iMi likely to fade from oiponire to the 
r. 

0rt0lH Orem.—Prwfctl astn either of the above 

mtiftB Ut ppMlacc A yollow ; but instemd uf a4d- 

|«f e^wi'fi^tia or Ibe brightt?ninK iKjuid, add ftfl 

' lie of indigo «a wUl produce the de- 



Amot^rr Orftm.^^VmoUc four ouncex of the 
b<M verdtfrrii, and np ^rccn and indigo half nn 
1 _. .1., ^ [tintaof the test riiieiear; put 



KentJy boil till the color 



I ' '>i« icrMm may be varied by alter- 

hy "It Af tfif* IfiirrMHenU j and I »}iould 

MruUr purnofe, to 

« veMtable color 

. , ,r ' '"■^-, '•* - ,...wa, wben expotcd 

A^?4/^' //«/_— T*; 1*0 povBdi of (tnuinn Braxil 

' wtiter ; put in ni many 

;i rover; boil them fur 

fM»m*i iwwn . tuKn iit)<i twu niitic'ti of alum, and 

MM ejHMQM of Moa-furtii, and keep it lukcwann 

unlfl M bne tUiuk throuirb. 

Amjikitr Jimd.mmTo every pound of logvood 

iwii intlloDi of water ; put in your 

i "l «n in tlie last ; Oicn add a suffl- 

t 111*- brifhteninfE liquid till yim bcu 

"' i keen the whole as warm 

tinker Ui it. till the color baa 






>dd 



rnili 



1 clti|waliould be [ucLed from fill 
iirra. with which it Kenerally 



fw 

alxmiMi., H> t.wrk. dirt, Ac. and it ia olwaya best 
when frcab rut. which may bo knowu by ita 
eiyearing of a bright rod color; for if atale it 
wul iook hrowB, and not yield lo much colorina 

Pvrptf —To two pounds of rhip logirood and 
bair a pound of Ilnuil dust, odd four pnltnna of 

wof'- ' ^''Tpnliinp in Tonrvcneci^ " 

f*" • li'iurfi; thun add p^ x 

?••' wo ounces of alum, k-i . ...i l,. ,. 

(oi iwu ui iht.ii hours every day, till the color has 
■tnick llmmirli. 

The H14/.1I ituflt only contribufes to make the 
purple ol a mijic red cast; you raav therefore 
omit it, if you rt^quirc a de*?p blueii<1i purj)Ie. 

Another /'Mrp/e.— Boil two pnundjp of logwood, 
either in chips or powder, in four pnllons nf vatcr 
with your veneers; aOer boiling till the color is 
well ntnck in. add Ijy dt-irreos sulphate of indigo, 
tilt the fnir|)lo i» of tht* Hhnde roquired, which may 
bo known by tryiiiff it writh u piece of psprr; let 
it ihon hoil for one hour, and keep the liquid in a 



i""l" 



Thi- 

wiUpwdare*;.. 
u IW fcftcfiMBf;, 

ChwHe.*-L«| lite reneera be dyed, byj 
ihc Mtfthodi porrionaly givcu. of a fine 
low, aad whtle they are still wet and 
with the dye. tnai&r til ' bi' 

tiU the color pUMtrmtea i 

Silmr Orrv— r,T.,^, ,u 

iron pot of - 
hoops. Ac, Hi 

of TiJiegar, and l«v uf ««tt;(, boit iitl wi 
hour; have your Tenc<*TS ready, which 
luf-wiKtd (not Uw dry.) put them in the c< 
use to dve btark, aud pour the iron li 
thrtn ; add om- nonnd of chip lo^^ood, 
ounces it-iraJIs; then boil nj 

put nf ; ^r ffi supply the co| 

ki M d, and boiling! 

a . color. 

iron, ur what n be: 

Ac, in any conver. . 

time, sprinkle thim with spirils of salt, 
acid, ) diluted in fi^tir times its quantity of 
they are very tLickly covered withrusl;- 
every six pounds add a gallon of water, i 
has brcn dissolved two ounces of snJt 
lay your reoecra in the copper. And covi 
with this liquid ; let it boil for two or thx 
till tfcU soaked, then to every gallon of li^ 
a quarter of a pound t.f groon cupperas, 
iho Mhole at a moderate icmperaiuiG till 
hnii suSicienLly penetrated. 



MISCELLANIES. 

Preparation of /7orir— Th? horn is 6nl 
over a firr made of thr ftslki of furxf . >%^ 
dvred soft, it ii slit on one side and kopt 
flut brtwern ■ pair of tongs ; it is then pie 
prots between iron plates which are gredse 
horiif ar^ suffered to remuin till they ar^ 
tiiey are tbeu suakeU in water till soft eaoi 

Eared down to the required thinners, wjtl 
uife woikeil horizoulally un 11 block, 
trarsparrocT is thus acquired ; and after fa 
mcr»ud xvi li>y,lhcyBfT poliibed niLh nbitei 
(he i.'oal of burnt MiUow. 



CORRESPONDENTS 

f.i 1 



A. B. — The llquiil uwfl f ■ ' • 
t'lilnrvd with nny V'-i ' 
Prukslnu blue. rttJ Cnl 

Mt'll^MCAr. IJHAtVIMfJ.' 
Itiit boHTil, up4>a tvluc)i (■' ' 
)i1:iiir 4(»|p. BDil a |tBtr nf d 



Sui r Unnkf 

W W.iort_Wt 
A Tvno — II in hi 

nrliclri. vf ce>ur-.i> iihto i« iti< 
A RKiiLir. tbalt b« advoded id. 



— rtK-lilneat 



r»^l 



■h >fttttiti<.<ii I 



CnrnmunlrnUoai, Books for Rcrifw 
tratioD. Ate. ta be addrc^svd !• Uu 
t*rr*cot Btrcvt -. \f> lb* Pdntsr ; or u> iu« ruui 
Latttn muft t>« pMlpaid. 



Frmteilby n.Fif 
fuliUiLeii pvi . 
\^ow , aoit niB\ ' 

Town and Cimoio 



THE 



GAZINE OF SCIENCE 



^n& $rf)Qo[ of Em. 



-vni.] 



SATURDAY, MAY 9, 1840. 



[Prick If?. 



^h 







ECCENTRIC TURNING.— SLIDE REST. &c. 



MAGAZINE OF SCIENCE. 




It wts obR^rved in page 11, when detcribuig the 
Ecooiiliio Chuck, that a peculiar slide mt wu a 
BMICMU7 «ppeiuUge to it, and also, a promiae wai 
given of tnfltnictions to condacC the aitul eccentric 
work, the object of the present peper is to ftilfil 
that promise. 

Stute Reat. — The Figtire in the present pft^ 
reprewmta thi; small sUile reiL. A, ia a tied or fooC 
which screws down \\\ the oswU manner to the bed 
of the lathe, and ditft* n in no respect whatever from 
that which holds the ordinary rrtt. in like matuMT 
it la famiiihed »ith s screw, It, which brhtens the 
upper part, which has a plug and fit* into a aoclcet 
in the upper put of A. u oioiL 

C C, u a piece of iteel, 4 or 3 inchcfl long, of 
the shape repre^rnted. with a groove along the 
middle of it, and graduated on one side In incli» and 
tenths of an inch, the groove should be of the same 
laagth as the height of the nose of the mandril above 
the bed of the Uthc, the whole should be aecrl; 
hiif sA bch In thieknest, and ground perflBclly true 
upon the fiwe uad sides, as the pert D moat aUde 
•ocurafeel; and emootbly backwards and forwards 
upon It. Thb psxi is moved b^ meens of a screw 
at (be end of C, which screw passrs alonfi; thr grcMTtv 
quite to the fikfthcr rnd, where It H% into a collar, 
SO thst when turned rciund bjr its ^nare hnul. it 
aOTM D* hankwards and CBrwarda, without cbsngicig 
ki own origlnil position. TIm letter D. is rnppoaed 
to rvprvwnt the whole part of the mschiiHr which 
slides upon C C, and whiob in like manner witli C 
U made of sleet : U U fumiabed beluw with a scxvw. 
wUeb At* th« «<:rvrw belonging to C, and on the 
nflncr part with two sMa pteers formiug a groove In 
nlJrb tba tool aUsr novas. Accuraqr of grinding 
U karo as nrSBonsry as faa the former Instance, as 
wMmA aqnabtUaf of esotlont ecevnine tunilog ean- 
not bo ooe omp Ha b fi l with any oertainty ttr beauty. 

Tlia tool sUder D, bas f«str»rd near one end a 
brass socbat. B, with a «iuarr bole quite tltrougb 
U boriwMlilIf and sKntgbt wltli its uls. TUs is 
IIm port where ttie tool Ati. and which U fastened 
doira by a serrw at top. Tb« baodHa la for the 
MrpDoa of dnwitt£ the tool tnm or to the nork 



supposed to be fixed to the ntnodril of 1W 
opposite the end of E. 

It is requisite that this paft abonU bo< 
iu action at pleasure, otberwUa bod tW 
timtt but the steadiness of the band upo* 4al 
it would cut sometimes more deeply «Kso si 
and all regularity would be destroyed I fcr \ 
compUshme nt of this (he Bcrrws r, 0» 
placed at the opposite end, as aftarws oi 

Tbo/*.— 'ilie tools are termed ol |<> ^<P 
about 2 inches long anda Uttle mofwftiaa«M 
of an inch in thidcDeas. the points of 
grown to certain sngtea, and of 
according to the particular Vind of 
which they an: intended. In whatever 
eccentric turning are to be printed frW(J> 
cesaary that the omaqjeots shuatd he 
feeUy fiat surfsoe* and oMislst mardy «f a 
Imesp such as in all thi ^rvasad fUoatnr 
this b bot the commonar kind of work 1 aa 
bcnntiful combtnalloft of wcU lalseCod 
beadhwB, groovea, and Unco of vasfooa 
of dtfbrtal alia may bo SMde m 
worked as aaaily as these. 

A^utlmmi.^Vxnt scra w th> 
npon the mandril . and also a coma 
upon this • fasten the pircw of boa timA 
msterial to be opemlrd Ujioo. Tuw dawn 
hce of the work until It ia 
ercB, that is ncitbi-r boUov nor 
Bsiddle, and it will be ready lar cMcaanr 
to be plaent u^ion lU Tbim P«l a * 
tool (that is otte shaped Uke ^ oft «f • 
the aochot at E. and fta It thvB «r«ay llf 
at top, and put tba tool alblso In Ua nlaaat. 
tbabedofUksrestfA, tothabodofOa 
Ita usual aortw, at awh a dWaaac trwm ' 
as for tha point of the tool noarfy m 

• U thMS •Urvclkm tl U 

(t>m m iSc-ciBUto af wmm n» • 

Ui« r«i»v»l ohvek Is 

wiU rsadUy —tf< ftSHnahm W 
e«asr dM^ 






MAGAZINE OF SCIENCE. 



43 



Kext, bj tltc a^jogtaient of 9 T Bqave, Mt tlie part 
C C, otactly panUd to the face of ttie work, and ot 
Boeb a fadgbt as for the point uf the tool to be In 
|Ae una tine as the centre of that work — fix it in 
phb position hj the icrev B. The next adjnetment 
Sfl to regulate the depth of the liDes to be cut. The 
>iBt of the tool nearlf tiniching the work, let 
F, be moved forwards antil it bears upon 
r the tool slider frame ; keep the tool up 
bj means of the handle, (rradaolly- 
■ screw F, until the line which the tooF 
soffirient depth ; when this is the case 
O, until tliat also touches the end of the 
sr frame, that is the traaiveriie slider, and 
this poiiition by turning the nut at H ; tliuB 
tbe tool up to the work at every circle until 
e« tbd alider, all the lines cut will be uni- 
deptfa and widdi. Should it he requisite to 
Tenr deep or the material operated upon 
hard, they may be cut gradually by the 
iployment uf the icrew P, otherwise P is 
useful^ nor any other adjustmant of the 
any part of the work necessary, unless a 
depth of line be required. The formation 
preaettt and foregoing examples will be 
' vadentood by a remembrance of tbe powers 
eccentric chuck formerly described, and the 
; directions, in which we are obliged to refer 
the present and former paper. 
K (present paper.) — Set the tool to cut a 
the requisite depth* and turn the screw at 
of C, (slide rest) till Uiu transverse 
paaaed over one inch, this of rourise will 
it 2 inches in diameter, turn the screw at 
the eccentric chuck four times rouni), 
the mandril in motion cut a cirrle, or 
part <^ one, that being all that is necessary 
Keeping to all these adjustments, turn 
of Che chack two teeth and cut a wcond 
Q it two teeth more and cut a third circle, 
on till the whole 48 are in like manner cut. 
ia complete, except cutting it aroand 



the edges of proper fdxe, and cutting the hole 
in the middle; these must be done by restoring 
the chuck to its first position, when it will b« 
without eceenthcity ; tbe size of tbe outer and inner 
rim being made by the slide rest, 

Et. 2. — Set the tool exactly opposite ifce centre 
and so prelected as tacut a deep hole in the cen- 
tre. — then set the tool to cot a ahollow line. Altev 
the eccentricity, (that is turn down the chuck 
half a tnm.) also alter the distance, (that Is 
the screw of the rest) half a turn from its cent 
position, and iC will cut a small circle, turn tht* 
wheel (always understanding the cogged wheel of 
the chuck) 24 teeth and cut a second circle, then 
another 24 teeth and cat a third circle, and finally 
24 teeth more, and then a fourth circle. The nejit 
row of 4 u made in the same muouer altering thft^ 
eccentricity and (lisLince, each another half turn 
Che respective screws. The third row require* 
another halftum uf each. The number of circles ia 
made by using the numbers on tbe wheel as before, 
and also one tooth of each side of them making a 
group of 3. In the neit row the circles are iti 
groups of 7, or three on each side of the ceuCral 
one. In tlte next the groups are in threes. In tha 
next the tool is turned back again one c6m. the ec- 
centricity increased and eve^ tootli of tJie wheel 
used, forming a ring, of 9C circles, so on for the 
rest. 

The other lUustrationa will readily be undentood : 
it is only refjuisite to remember that the depth of 
the lines, and the size of the circles depends upon 
tlie slide rent, and their eccentricity, nombcr, 
grouping in all instances arises from the adjui 
meuts of the chuck itself, whose combinations art 
endless. 

We have an anxious desire to illustrate in a simi- 
lar manner the other compound chocks, but not 
poeseuisg them, and there beins no work in £ug- 
lisb on turning, we fear such will be beyond our 
power, unless any friend will oblige us witli specio 
mens in Ulustratioa of thora. 



las 



OP STEAM AND 

ATMOSl'HEKE. 



OF TUB 



^^hatoB FoaB£s has read to the Royal Society 
^^HlBburgh two communications, of which Uiti 
^Mllnff Are abstracts. 
The antiior incidentally remarked, that the 
of thii sua wen through vapour issuing from 
■■ Bilely'Valvc of a luLnmolivir onyinu is doop 
Uy similui to that which a column of 
or BDokod glaas gives to it. 




He next noticed fiiat this colorific character of 
slcam extended but a short way beyond the 
vriiicc, and that It gradually became more opaque, 
and pericctly white like noon-day clouda, both for 
transmitted and reflected light. At a .modwtatc 
thickness, in this state, itj opaxrity is completa^.^^ 

These observations have been fully coofirtned 
by direct experiments on high-pressure steam. 
At the moment of issuing from the steam-cock, it 
is pcrfecUy tmnsparont and colorless; at some 
difiioQce from the orifice, it bocomes uonspArcat 



MAGAZINE OF SCIENCE. 



and onnge-rud ; bat, still (afth«r off it is white, 
and merely tmnsluccsu Thew properiics were 
(raced in stvam frura a prewnre above thai of tlie 
Atmosphtrro of 55 Iba., down to tn excesa of only 
Ibxee or fimrj and, as in all oases the reduess uf 
the Iranstnitttrn light wu more or loss difltiudly 
iwcn, (aud an oxi:ces of lU or 15 lbs. does us well 
OS any higher pressure.) it wiu concluded thai tho 
effect of partial coudeusaliun in pruductiig the 
phenomenon ''It^ould bo rc-odered visible in great 
thickness of vapour of the lowest icnsion. 

Th(j great analogy of the color of steam to that 
which llie clouds assumo at sun-set, or distant 
KgJits in certain conditions of the atmosphere, 
led the author to surest this singular property 
of cundcnsitig Tapoui as the probable cause uf 
thuHc phenomena, of which no satis&clory ex- 
pltuiatiuu cuuld be given whilst this fact remaiuL-d 
unknown. The crognostics of weather derived 
from the colors of the sky also feceivc clucidaiiou 
from the fact. 

Judging from tho Bimllarity of color of steam 
and that of nitrous acid gns, aud the remarkable 
power of absorbing certain definite rays of the 
spectnmi discovered in that gas by Sir David 
Brewster, tho author thought it probable that 
similar lines nii^ht bo discuvered iu the tipeotmm 
formed by light transmitted through steam ; cud 
that iJicsc inif:ht be found to coincide with the 
atmospht'Hc Unes of the speclmm noticed by the 
aame pbilusopher. llio experiment was made 
witli pTvM care, but the expected result has not 
been liilherto obtained. The general action of 
steam on ihesprctnim is to absorb the violet, blue, 
and yellow rays, Anally, leaving only the red aud 
o range, with an imperfect preen. 

Since a portion of watery vapour in a confined, 
space, otipir?iitly trnnttparent and ctdorless, may 
become, byrocio change of temperature, tirat deep 
urangc-rcd and transparent; aud, tiually, while 
and Bcmiupamie ; tho author notices another 
analogy with the singular effect uf lempemlure in 
deepening the color of nitrous add gas, and thinks 
that Uiese facts may one day throw some lorthL-r 
light on the djfhrult sutijii-t of t}ie mechanical 
Constitation of vapours, and particularly of clouds. 

The object of the second communication wot 
to devclope an application of the above fact, Tho 
discovery that Rlcam in a certain stage of con- 
densatiQU is deeply red colored for traniiuiitted 
light, seemed to uiTei a probable sululion of a 
dtfflcalty whicli has never yet been fairly met, 
namely, ihu rod color uf clouils at sunset, and the 
redness of light truusmittcd through certain kinds 
of fogs. 

A pretty full history of thcuries proposed to 
account for the colors of the atmosphere was first 
given i it being obtained almost in every caso Irom 
an examination fif the original authorities. These 
theories were reduced under three general heads, 
exclusive of that of fiiicthe, and of mu*t writers 
befijro Newton, that the blue color of the eky 
results I'rum a mixture of light and shade; and 
tliat of ^tunckc, that tliat color is merely sutfjectivct 
or arises from an occular deception. Tho remaining 
iJieorios arc : — 

1. That the color of the sky is that transmitted 
by pure air, and that all the lints it displays are 
modtficAtions of Uie reltected and transmitted 
colors. This is moiu or loss completely the opinion 
of Moriotte, Bougiier, Kuler, Leslie, and Br&ndes. 

2. That the colors of the sky arc explicable by 
floating vapours acting a» thin plat«t do. iu ru- 



^•uniii .iiLiiaLii-. 



i^|H 



fleeting and transmitting 

This is tbe theory of NcvttRi~«nd mott of 

immediate followers, sod niotv l«taly of Kobi 

3. On the principle of opaietccnce and of 
specific abs*»rptutn. drprTidin? on thr Timfyrp and 
unknown coi 
head is iutc'i 
of MelvilJ, i)^... 
Brewster. 

To the lost named philosopher, howevei, 
merit is due of having conspicuously tuned 
tentiou to the important, com;*U-T. apd htlhi 
unexplained phenomena of al 
has proved tu be totally iucQiu> 
theory of the rolur^ of natin 
those of thin plates;) aud ht 1> ~ 
strated the inapplicability of it :l .1 
colors of the atmosphere, by showmg i ' 
conslitutiuu is whuUy distinct from tli 
any modification of Newton's theory wou 
by a series of experiments, of which nii 
xesults un!y are announced. 

Since, then, the constitution of the atir 
Colors aualyzud by the prism resembles i 
duced by absorption,, the question is, to 
medium are we to refer that absorpUvo 
Evidently not to pure air, since a 
red in a fog, and in clear weather wl 
so. The author u disposed to attribute 
to the presence of vapour In the very act of 
donsation. This intenn«diato or 
occurs between tlie colorless and 
of steam whoUv uncondensod ; and 
may be termed the state of pnximaU 
in which it is seen to issue fVom the ipoui 
when it is likewise colorless^ but 
During the transition, the steam becomoi i 
red, and lemains transparent. The a1 
action resembles then, so far, that of the 
phere observed under certain meteorulogioal 
ditions ; the dark Imes and bands noticed by 
David Brewster in the atmospheric spectra fa&va 
not been discovered, and m Uit the onaiogy it •• 
yet imperfect. 

In applying this theory to the colors of suneeC in 
particular, the author quotes many aclcnowledgcd 
ucts to prove thai the redness of the sky Is 
developed precisely in proportion to the probable 
existence of vapour in that critical stage of con- 
densation which should render it colorific. And 
he appliee the same reasoning lo account for the 
prog:uostic8 of weather, drawn from the re« 
the evening and morning aky. 



SILKWORMS, 
THBIR Lirn, PRonuci, ANn majiaakmi 

ToK silkworm, called by entoraologista 
bumbyx mori, is like its kindred species, sal 
four metamorphoses. Hif rgi^, fostered 
genial warmth of spring sends forth a 
which, in its progressive enlargement, casts il 
either three or four times, according to the 
of the insect. Having acqoired its full sixe la tlm 
coarse of 25 or 30 dnys, and ceasing to eat dBring 
the remainder of its lite, it begins to dischat^ • 
viscid secretion, in the form of pulpy twia 
from its nose, which harden in ^e air. 
threads arc instinotively oolled into on ovoid 
round itself, called a cocoon, which sem» 





dtfcncg Bfainst U^og^ enemie:^ and changi>9 of tem- 
pcntare. Here it soon ebonies luto the chrysaliA 
or DpDph Atate, in which it lira swadiUcd^aA it were, 
for about IS or 20 dayi. Then it bursts its cere- 
mcsita, and nimea forth fumiibed with appropriate 
wtttga, sntennc, and feet, for living In ita new ele- 
nmtU tfar ntmoBphere. The male and the female 
nntfaa coople together at thi* timr. and trrminate 
ttdr naiOD hy a speedy death, their whole existence 
befn|[ limited to two months. The cocoons are 
eompletf'ly formed in the ooarae of three or foar 
days ; the tineet being reserred as seed wonns. 
From tbese cocoons, alter an interval of 18 or 20 
dap. the moth makes its appearance, perforating 
ita tomb by kDockin; with its bead ofainst oDe end 
of the eocooQ, after softening it with saliva, and 
thw rrodering the filaments more easily torn as- 
9tad«t by its daws. Such moths or unrelias are 
DoQected and plao!^ upon a piece of soft doth, where 
dtfy coaple and lay their eggs. 

The rggs, or grains as they are osoAlly termed, 
are enveloped in a liquid which causes them to ad* 
hoc to the piece of cloth or pajKr on which the 
lays tJiem. From this glue they are readily 
by dipping them in cold water, and wiping 
ttem dry. Thty arc best preserved in the f/vum 
stite at a temperature of about 55^ F. If the beat 
of spring ailvancea rapidly in April, it must not be 
foffereJ to aict on the eggs, otherwise it might hatch 
(he caterpfnan long before the mulberry has M&t 
iorth iu leaves to nourish them. Another reason 
tor kncping hack their incuhation is, tliat they may 
Wbatcfaed together in large broods, and not by 
tnaU aombcrs in soccesaion. The eggs are made 
tf tntA small packets, of an ounce, or somewhat 
mm9t which in the south of Prance are generally 
ttCaobed to the {snrdles of the women during the day, 
sad pUoed under their pillows at night. They are, 
«f OMirae, cnrefully examined from time to time. 
la large establishments, they are placed in an 
Ippnprlate stove-room, where tliey are exposed to 
ft tuBparature gradoally increased till it reaches the 
0(di Jj^mi of Fahrenheit's scale, which term it 
■Ml not oteeed. Aided by this heat, nature com- 
fktUa her mysterious work of incubation in eight 
w Cm days. The teeming eggs are now covered 
vtidi ■ sbe«^t of paper pierced vrith namerDUS holes, 
atoul oDC-tweUUi of an inch In diameter. Through 
syqr tnr ea the new-hatched worms creep up- 
inscinctiTely, to get at the tender mulberrj 
Ut*m itrinred over the paper. 

The nanery where the worms are reared, is called 
by the French a maijntniih-e ,- it ought to be a well- 
•irvd chamber, free from damp, excess of cold or 
hmfc, rats and other vermin. It should be ventilated 
oeaskmally, to purify the atmosphere from the 
mi some emaaatton« produced by the excrements of 
flf d» caterpillars and the decayed leaves. The 
of the wicker-work shelves should be 
: and they should be from 1& to 1 8 inches 
SfMft. A separate small apartment should be al- 
h U Hd to the sickly worms. Immediately before 
mA ascmliang, the appetite of the worms begins to 
Alg; U eeaaes altogether at that [leriod of cutaneous 
■■lamflr|)hosis, but nrvivea speedily after the skin 
ll Mrif eeet, because the internal parts of the ani- 
■■1 are thereby allowed freely to develop themselves. 
At tht csid of the second age, the worms ore half an 
fasll long ; and should then be tranaferrtrd fruni the 
i^bD room in which they were ftrst bntchcd, into 
Iha proper apartment where they are to be brought 
la aitenty and set to spin that balls. On occaatoa 



of changing their abode, they must be weD deadeed 
from the litter, laid ut>oo beds of fmli leaves, and 
supplied with an abundance of food every six hours 
in succession. In shifting their bed, a piece of act- 
work being laid over the wicker plates, and covered 
with leaves, the worms will creep up ovetr Ihem t 
when they may be tnmttferrcd in a body upon the 
net. The litter, as well as the sickly worms, mmj 
thus be readily removed, withont handling a single 
healthy one. After the third age, tbey may be fed 
with entire leares; because they are now exceedingly 
voracious, and must not be sufasefjuently stinted in 
their diet. The exposure of chloride of limr, spread 
thin upon plates, to the air of the mafptanihej baa 
been found useful in counteracting the tendency 
which sometimea appears of on epidemic disease 
among the silkwomsi from the fetid exhslatiooa of 
the dead and dyii^. 

When they have ceased to eat, dther in the fbvftK 
or fifth age, agreeably to the variety of the bombjfx, 
and when they display the spinning instinct by 
crawling up among the tvrigs of heath, Sec, they 
are not long in beginning to construct their cocoons, 
by throwing the thread in different directions, so aa 
to form the floss, tiloscllc, or outer open network, 
which constitutes the l/ourre or silk for carding and 
spinning. 

The cocoons deettned for filature, most not be 
allowed to remain for many days with the worms 
alive within them ; for should the chrysalis have 
leisure to grow mature or come out, the filaments at 
one end would be cut through, and thus lose almost 
all their value. It is therefore necessary to extin- 
guish tlie life of the animal by heat, which is dona 
either by exposing the cocoons for a few days to 
■onshine, by placing them in a hot oven, or in the 
steam of boiling water. A heat of SO'/' F. is suf- 
ficient for ofTecting this purpose, and it may be beat 
administered by plunging tin cases filled with the 
cocoons into water heated to that pitch. 

80 pounds French (8S Eng.) of cocoou, are the 
average produce from one ounce of eggs, or 100 
from one ounce and a qaarter ; but M. Polxer of 
AUace obtained no less than 165 pounds. The sUk 
obtained from a cocoon is fVom 750 to 1150 feet 
Long. The varnish by which the coils are glued 
slightly together, is soluble in warm water. 

The silk husbandry, as it may be called la com- 
pleted in France within six weeks from the end of 
April, and thus aflbrda the most rapid of a^cultu- 
ral returns, requiring merely the advance of a little 
capital for the purchase of the leaf. In buying op 
cocoons, and in the filature, indeed, capital may be 
ofteo Laid out to great advantage. The most hazard* 
ous period in the process of breeding the worms, is 
at the third and fourth moulting;, for upon the 
6th day of the third age, and the seventh day of the 
fourth, they in general eat nothing at olL Oa the 
first dny of the fourth age, the worms proceeding 
tt0m one ounce of eggs will, according to BonaftmSy 
consume upon an average twenty-three pounds and 
a quarter of mulberry leaves ; on the first of the 
fifUi age, they will consume forty-two pounds ; and 
on the sixth day of the same age, tliey acquire their 
maximum voracity, drrouring no less than *223 
pounds. From this date their appetite continually 
deereases, till on the tenth day of this age they 
nnnsume only fifty-six pountU. The space which 
they occupy upon the wicker tables, being at their 
birth only nine fiset square, becomes eventually 239 
feet. In general the more food they coosmue, the 
more silk will they produce. 



A 



MAGAZINE OF SCIENCE. 



: 



A raulboTT-treci U Tiloed, In ProTcncc, at from 
6^ tolOd.i it is planted out of tbe nurscrir at four 
joan of age ; it ia begun lo be stripped in the fifth 
year, and afTorda an increaaing crop of leaves tilt 
the twentieth. It yields from 1 cvt. to 30 cwt. of 
leaves, according to its magnitude and mode of cul- 
tivatioa. One oonce of silkworm egga ia worth in 
Prance about 24 &mooB; it requires for its doe 
claTelopment inio eocooaa about 15 cut. of mul- 
berry leaves, which cost upon an avenge 3 
francs per cwt. in a fiBLVourable season. One 
ounce of eggs ia calcnlsted^ to produce from 80 to 
100 pounds of C0C0008, of the value of 1 branc 52 
oentunes per pound, or 125 francs in the whole. 
About B pounds of reeled raw silk, worth Iti franoa a 
pound BfeobtBtnrd from these 100 jwunds of cocoons. 

There are three denoatinatioua of raw silk ; vis., 
organsine, frame (shute or tram), and floes. Or. 
ganztue serves for tlie warp of the best silk stnflis, 
and is considerably twisted; tram is made usaally 
from inferior Bilk, and ia very slightly twisted^ in 
order that it may ipread more, and cover better in 
tiie weft ; flofls, or 6owt«, oousista of the shorter 
broken silk, which is carded and span like cotton. 
Oi^aozine and trame may contoiu from 3 to 30 twin 
filaments of the womi ; Che formt^r possciHea a 
double twist, tbe component filamentig being 5r8t 
twisted in one direction, and the compomtd thread 
in the opposite ; the latter receives merely a slender 
single twist. Each twin iilament gradtuUy dimi- 
niahes in thickness and strength, from the snrface 
of the cocoon, where the animal begins Its work in 
a state of vigour, to the centre, where it finishes it, 
in a state of debility and exhanation ; because it 
can recdve no food from the moment of its begin- 
ning lo spin by spouting forth its silky substance. 
The windier b attentive to this progressive attenna- 
tion. and introduces the commcucement of some 
cocoons to compensate for tlie terminntion of others. 
Tbe quality of raw silk depends, therefore, very 
much upon the skill and core bestowed upon its 
tUalure. The Boftest and purest water should be 
used in the cocoon kettle. 

Ttie quality of Che raw silk h determined by first 
winding off 400 ells of it, round a drum one ell in 
circumference, and then weighing that length. Tbe 
weight is eoipressed in grains, 24 of wliicti constitute 
one denier ; 21 deniers constitute one ounce ; and 
16 ounces make one pound. This is the Lyons 
rule for valuing silk. The weight of a thread of 
raw silk 400 ells long, is two grains and a half. 
when five twin filamenta have been reeled and as- 
sociated together. 

Raw lilk is so absorbent of moisture, that it may 
be increased t«n per cent, in weight by this means. 
This property has led to falsifications ; which are 
detected by enclosing weighed portions of the sus- 
pected silk in a wire-cloth cage, and exposing it to 
a stove-heat of about 78° F. for 24 hours, with a 
current of sir. Tbe loss of weight which it thereby 
nndei^oes, demonstrates the amount of tbe fraud. 
There is an office in Lyons called the Condition, 
where this assay is made, and by the report in 
which the silk is bought and sold. The law of 
France requires, that all the silk tried by the CoTuii- 
thtm must be worked up into fobhcs in that country. 

In the Journal of the Asiatic Society of UeugiU, 
for January. 1B37, there are two very valuable 
papers upon silkworms ; the first, upon those of 
Asaam, by Mr. Thomas Hugou, stationed at Now- 
gong; the second by Dr. Ilelfvr. upon those which 
are indigenona to India. Besides the Bombyx fnori, 



t})e Doctor cnumenites the following seven spedv. 
formerly unknown : — 1. The wild dlkworm of the 
ceniral pnjvinues, a moth not larger than the Ana> 
b^s ntori, 2. The Joree silkworm of Amsol, 
Bomby* rtlipioMt wldch spins a cocoon of a finv 
fihunent, with much lustre. It lives upon the pipul 
tree Cf^eiu rtligiota)^ which abounds in India, and 
ought therefore to be turned to aooovnt in breedlag 
this valuable moth. 3. Sahtrnim titkelictt^ which 
inhabits the cas^ mountains in Silhet and Daooa* 
where its large oooooni are spun into silk, 4. A 
still lar^^r Hatttrnia^ one of the greatest moths In 
eiistence, measuring ten inches from the one end of 
the wing to the other ; observed by Mr. Grant, in 
Chirm PuajM, 5. fta^trmiajHtpkiafOr the Ttttseh 
silkworm, is the most coounon of the native epedM, 
end furnishes the cloth usually worn by Europeans 
!a India, it has not hitherto been domeoticatedi 
but miUions of its cocoons are annually ooUectcd In 
tha jungles, and bruoglit to the silk factories nasr 
Calcutta and Bhagelpur. It feeds most eomnumly 
on tlie hair-tree (ZizypkuM jujuba)^ but it prcfca 
tbe TVrmtnaJid alata, or Assam tree, and the Bomm 
byx hepii^hyitvm. It is called Kouthiri i»oc^a,lD 
Assam. G. Another Satumui, firam the ncighboo^ 
hood of ComercoUy. 7. Satumia ajmamenaU, with 
a cocoon of a yellow-brown color, different from all 
others, called moo^o, in Assam ; which, althou^ it 
can be reared In houses, thrives best in the open air 
upon trees, of wluch seven difTereut Idnds adbrd It 
food. The MaxmUctjor^ mnaga, which fu^s on thfl 
Adakoory tree, produeei a fine silk, which is nearly 
white, and fetches 50 percent, more than the Cswn- 
colorcd. The trees of the first year's growth pro* 
duce by far the moat valxiable cocoons^ The mooga 
which inhabits the soom-tnee, is found principally 
in tbe forests of the plains, and in the villagas. 
llie tree grows to a Urge size, and yields tbrrs 
crops of leaves In the year. The sUk is of a light 
fawn color, and ranks next in value to the Masas- 
koory. There are generally five breeds of moogi 
worms in the year : 1. in January and Pebruaxy; 
2. in May and June ; 3. in Jane and July ; -L. in 
Auguat and September; 5. in October sod Notsm- 
ber ; the first and last being the meet valuable. 

The .^asamesa select for breeding, such ooeoou 
only as have been begun to be formed in the largest 
number on the same day. usually the second or Ihiid 
after the commEncemcnt; those which contain Qkalee 
being distinguishable by a more pointed end. They 
are pat in a closed basket suspended from the roof; 
the moths, as they come forth, having room to moit 
about, after a day, the females (known only by their 
large body) are taken out, and tied to amaU wi&ps 
of thatching -straw, selected always from over tiic 
hearth, its darkened color being thought n&orr ac- 
ceptable to the insect. If out of the batch, then 
should be but few males, the wisps with the fiemaks 
tied to them are exposed outside at night ; and tha 
males thrown away in the neighbourhood find thcEr 
way to them. These wisps are hung upon a string 
tied across the roof, to ae^ them mnn Tccmia. 
The eggs laid after the first three days are sud (Q 
produce weak worms. These wispa are taken ool 
morning and evening, and expoaed to the BuaahiM* 
and in ten days alter being laid, a few of them are 
hatched. Tbe wisps being then hung up to tiba 
tree, the young worms find their way to the IciaTCs. 
Tlie ants, whose bite is fatal to the worm in its early 
stages, are destroyed by rubbing the trunk of the 
tree with molasses, and tyiug dad fish aud loads to 
it, to attract tlu»e rapacious insects in large nam- 



MAGAZINE OF SCIENCE. 



47 



b«rt, wbm thrj- are destroyed with flre ; a proceia 
vUch need« to be repeated flCTeral times. The 
fffKind ooder the the trees is also well cleared, to 
RDder It e&ry to pick up and replace the worms 
wUch bll down. They are prerented from oomlng 
to th« ground by tying fresh plan tain -leaven round 
fW tmakt over whose sUppery surface they cannot 
tnw\ ; aad they are transferred from exhansted 
tnea to fresh ones, on hamboo platters tied to long 
poles. The worms require to be constantly watrhed 
and protexrted from the depredations of both day and 
ai|bt birds, as veil as rats and other vermin. Du- 
tiiV their moultings, they remain on tbo branches ) 
hot when about bejpnning to spin, they come dowa 
tilt tnuik, and bein^ stopped by the plantain-leaveji. 
•nt tbrre collected in basketSi which are afterwards 
pat under banches of dry leaves, suspended firotn 
tho roof, into which the womn crawl, and form 
Uwif cocoons — several bcin^ clustered tof^ther; 
this arrident, due to the practice of crowdini; the 
vonna together, which is most injudicious,renilerlng 
it fanpoasible to wind oflT their silk in continuous 
Aresda, aa in the filaturea of Italjr, France, and 
f««0 Beo^. The silk is, therefore, spun like 6ax, 
tnlaad of being unwound in single filaments. After 
fnr days the proper cocoons aro selected for the 
nest breed, and thereat are uncoiled. The total 
' : 1 of • breed varies from 60 to 70 days ; 
i:ito the fisUowing periods: — 

I'Dur moultings, with one day's illness attend- 

bigeach 20 

fun fourth moulting to beginning of cocoon 10 
U the cocooa 20, as a moth G, hatching of 
a|ga to 36 

66 

Cd bdng tapped with the finger, the body ren- 
ders a hoQow sound ; the quality of which shows 
■ksther they have come down for want of leaves on 
the tnv, or from their having ceased feeding. 

'.'■ rhrysalia is not soon killed by exposure to 

the cocoons are put on stages, covered up 

III itTMii-*. and rrposed to the hot air from grass 

under tliem ; they are next boiled for about 

nkrar in a solution of the potash, made from In- 

cbnted rice stalks ; then taken out, and laid on 

ddtt folded over them to keep them warm. The 

tOBS being removed by hand, they are then thrown 

iite a burin «f hot water to be unwound ; which is 

4mb ta a very rude and wutefol way. 

Tte pUutulions for the mooga aUkworm in Jjower 

, amount to 5000 acres, besides whnt the 

eoutain ; and yield 1600 maunds of 84 lbs, 

*^ i>er aanoro. Upper Assam is more productive. 

>cooa of the Kotttkuri monga, is of the site 

'■'s 1^. It is a wild specicfl, and affords 

CuuulJ oiach valued for fishing-lines. 

%4 Tha Arrindtt, or Bria worm, and moth, is 
tmnA over a great part of Hindustan, but entirely 
■lUlis doors. It is fed prinripnlly on the Ifvra^ or 
Ps^Mtn c/,T<\ti leaves, and gives sometiioes 12 broods 
r: the course of a year. It affords a 
> jka rough at first ; but when woven, 
bawaira Vi!i and silky, after repeated washings. 
Ihl poorest people are clothed with stuff made of 
lla vbcb is so durable aa to descend from mother to 
tesbter. The cocoona are put in a closed basket. 
Dp in the house, out of reach of rats and 
When the moths comu forth, they are 
Co mof e about in the basket for twenty-four 
i after which the fcnules ore tied to long reeds 




or canes, twenty or twcnty.five to each, and those 
are hung up In the house. The eggs that arc laid 
the first three days, amounting to about 200, alone 
sire kept ; they ore tied up in a cloth, and suspended 
to the roof till a few begin to hatch. These eggs 
are white, and of the size of tuniip-secd. When 
a few of the worms are hatched, the cloths arc put 
on small bamboo platters hung up in the house, in 
which they are fed with tender leavea. After tlie 
second moulting, they arc removed to bunches of 
leaves soKpcndcd above the ground, beneath which 
a mat is laid to receive them when they ftll. When 
they ceaae to feed, they are thrown into baskets 
full of dry leaves, among which they form their 
cocoons, two or three being often found joined 
together. 

9. The Satumia tri/rnet/rata, has a yellow 
cocoon of a remarkably silky lustre, ft lives on 
the sooni-tree Ln Asaom, but seema not to be 
much used. 



SUMMEB DRINK8. 

Ginger Seer in bo4tte$.—Vai into any Tcsael 
1 gallon of boiling water. 
1 pound of common luaf sugar, 
1 ounce of best ginger, (bruised) 
1 ounce of cream of tartar, or eUo ft lemon sliced. 

Stir them up until the sugar ia diitfulTod, lot it 
rest until about as wann aa new milk, then add 
one tahlc-spoonful of good yeast, poured on to a 
bit of bread put to float on it Cover (he whole 
over with a cloth &Dd sutfer it to remain undis- 
turbed 24 hours. Then strain it, and put into 
bottles, observing not to pot more in than will 
occupy thrcc-4|uartcr3 of ihcir capacity, or as wo 
usually say tUrcc-quartcra full, cork tiio bottles 
veil and tic Oic corks, and in two days in worm 
weatJior it will bu tit to drink. If nut to be cou- 
flumcd till a week or fortnif^ht after it is made, a 
quarter of the &ui!B.t may be spared. The abovu 
quantity of iugrodicnts will mikko IB bottles, and. 
cost 1(J pence. 

Common Ginger J?<«r.— 'That common drink 
sold in the stieettf, is mode with raw giignr or 
treacle, half a pound to the gallon of water, tho 
ginger ground and without uio acid, coating odo 
farthing per bottle. 

Lemonade in botUeJi. — Tliis diflera in no dcgroo 
in manufacture from ginger beer, the ginger biting 
loft out, and IS drop^ of llio essence or of the oil 
of k'mou beinp first ground up with the sugar, — 
tlio essence is tho same oa the oil of lemon but 
mixed witli spirits of wine, it thereforo unites 
readily with tho other ingredients, nnd Id moro 
convenient in uae. 

Soda Powciert, are tartaric acid and carbonate 
of soda. Procure an ounce of each, and divide it 
into 16 portions, wrap up the acid in oitu colored 
paper, and the soda in another, (merely for tho 
soke of distinction when used.) dissolve one of 
each kind in half a tumbler of water, mix the two 
solutions together and take it immediately. 

Tlie above metliod of mixing is very ineonre- 
nicnt because the cfTcrvescDnco is so rapid that it 
overflows the gloss, it is better first to ilissolve tho 
Boda in all the water, then add the acid in puwder 
and drink immediately. Using equal quantities 
of each material, the drink will be slightly acid, 
which to moBt potsoaa is agreeablo; oithc aoid 



48 



MAGAZINE OF SCIENCE. 



wmj be vaui iaiUad of the tartvic^ and viU b« 



iTe one ounce of 
cf Mdfc an ft paUon uf vaier, pat it 

. is Uw vmantily of a tumbler foQ or 

telf ft pot io eadi ; uviac the cork recdv, drop 
tato Mck boCUe hfttf ft dnram of tartftiic ur citric 
■jiM la ujiiib. catk ft»d mr* il mmi^wtcly ftttd 
ift«illaiw4TiBmeataB5tfM. 

l^B^^ Nwdwv.— Poud ftsd ButogetWr 
WC ft |««b4 «f bftf ftVCftr* 

ft^A iknc « few iropft of tiht o« cf I 
■to 16 



100 pftiu conuin 30-13 
tide of nirkel U diuoh 







jgnilrd if vvi^died 
tftUic line, i he pcmxii 
in hydro-chlorir acid. preriptiiUed by cftu 
fiJterrd off and we>i|^t*d : 100 pafU 
78-71 of netftlUc nickel. 
T^ vrpftntiaa of nickel and tine is ev^ 
tended with difficnltj and runie imcertiuiitv, 
morcr simple by ibo mVl 
[ vhicb IB not m<.'re tnaccni 
Bcf:>ro weighing any of 
«ibav«os>dei,iCiftiftecidfrdlypreftnihrelo bum 

off ftB much t>f tliL> suh 
ft* pvaAlt bto ft pUiianm crucible; to atld ihf 
MM^ lai AiB Mfctnct their weigbt fxom duit of 



HI9CELLANIKS. 

— Da. Uai bsTioi; t^Wni in ob 
tWistcnaiue* uf difTprfat li^'htf, 
•f ifctf wlfttiveihAiIuwi \hvj pn^ 
btlMviBg photumruic 
M mtmmi pMcti of p«p«r. prep 
fl/^dMrii nr the pbouigcoic drai 
ftftf ft koaac JA^ned by a high 

the vioJovi ; ftnd &lsn ia i 
hoaie not •>> circumstaoccJ. 
espmcHJ to the action of 
a rvrtain depth of tint ; and 
10 rxinired to pn>ilurf the 
i BftVpftport placed in the rlnrk^-upd i 
P»^ Cm mm ■aafcltil to demmioe Ih^ 
^I^ m ftfttftiahftJ, By pbotop-: 
Ma^ Dk. Dm oomaAtn the relalivo 

ib differeot roiinu ip aoy houaf 
or OD diffrreuL dnva lo 
cooftlr;. also the extent or slreoj 
«( 4a;]Sffcl ia aay part of the wurlJ, — may 
* ftM ifgiiteied. 



CORRESPONDENTS. 

« JL^iOb* ■■ ■ ■ » < «« «• ottOfvd te. larf *tll tMot It I 




AIM ^ WttU^ Vf U>M. 




kiawr BUL 

*T Gu-viKMa, — Tta wlr* «mS 

■n k* vmit^4 pMtUDj or whaUr i»«iid Ik* har of 
» |iM iMft rrj wa mOm for ■ hmO Iw. 



%'mt. i,^tki$ i&yftriitr it nom nmfy, bmmd U 
Owrrt, OrtitreJj, for hmdimjf^ auy oiao It 



fl— laaltallwiii Beahi tir lt**tew. lavfatten 
ftc. to bt i VIf w d lo tW EkMor. M 

In Ac rilliij a> to Ike Pvblliftv. 
UMMt MOM W pMl payi 



mua ^dfuiiia 




ELECTRICAL INDUCTION AND DISTRIi3UTI0N 



ipi«d ti; the electric fluid th*C is inberrDt 
boiijes. There Bppean reasoa Co cooolude 
^Ol0 wbote lUMttrr at which any sabfttanco i> 
equally imbued with this sobtile 
Uet is proved by the Uw of eleclri- 
uid oUo that by galvanism and 
m great and continuoui a itrcam is 
.. It. 



proilaccd. It U aUo no less demoiutrmbI«, Ihfit we 
con by the violent and sudden trinefermce of a 
stream of free electricity, or u it Is callod a shock, 
diMurb the lluid iu the inner portiuns of whatever 
condnclur we have used as the means of comuiuoi- 
cation between the poles of the battery, and this 
ec|aally well whether the surface! be expoted or not. 
This is disputed by other electridans. wbo main- 
tain that electricity resides ouiy apon the surface of 
excUed or chargad bodies. Wc will give an ajwri- 
ment or two, and then make a few remarks ajMa 



w 



MAGA2:iNh OF SCIENCE. 



end!! of Ihne oi^niont. The first ms fqpported 
1)/ Cavallu. who givr> the ioilitwin^ : — 

Kr. 1. — Talte a wirt nf nnj Viatl uf metal ftud 
cQTtr part of it with some electric ■abttance, ai 
msto, ualiog-wax, Ike., then diichariB« a jar 
through it ■Oil it will be fon&U ttini it roD<Saets M 
well with u vithout the elrcirii- coaling, Ibia pnives 
tliat the elertric Tuid iia>»c5 through the tnlj^UDoe 
oLthe metal, and not urrr its flurfacc 
^Ex. 2. — Let a penoD hold tlie vire connected 
with ons surface of a charge*! hntterr in "ne hnnd, 
aod toach tbeoth'ir surface with the ci ^ .- 

ehock will xnits not over \\ii >>ih1j, b.r /., 

and afi'ect hiiu in the wriats, arma or cheat, accord- 
ing to iia strength. 

Although the*e exptriments prore that in rioleot 
cases the electric fluid Vaj be aiadr Co jiats through 
Uw! interior of bodi«, rtt it hy no means implies 
that when charging a hcdy vitb rtcctricitr, we 
neccsMrilf drire it beneath the snrfece; on the 
contrary, both reaft' ■ "vcihat 

in the uMinary tr tion of 

the fiaid, It re«ide» ■ -i .... ...^ r....... . Pncatly 

and CataUo prored this in former linirt. and 
(Viuloinh. l<v thr a^tUnce of hia odmirBhle and 
dt" v.T.^iee Vol. 1.) has «»n- 

(ir ! ■i[K>«!tir»n. und proved the 

tn.' ftttitt cofM^tr 

t,j <■ tratu/ertncr 

a« lu proj-vrrmfi t i inr *7ir/f ,,t •,/ a ittifiy^ €Md no/ 
mv^rdnir '» </* toluIUy." Thus n hollow condoctor 
IS alvaya m eCficacious tis one which is solid. A 
large conductor will accumulate more than a small 
one of more solid materials. 'Hie power uf n Ley- 
den jar is in proportion to the surface, and not to 
the thiekneM of the glass— -and so on in numberisss 
other ftimilar in^tanc^i. In fact it msy be said, 
that altbou^h the glau rods used as supporla to 
any parts vf t)ic apparatus art usually made solid 
for the mIp of 5trcn::;ih, yet the thinner glass 
cylinderji, jarr, conduciun, Slc., are made» osually 
the bettrr the machine worka . 

The following eiperimenta will be read with in- 
terest. 

fir. 3. — Support upon a glan rod a wooden ball, 
and bore Torious bolet to dtfTerent deptlia upon its 
snrfacc, as repreaenlcd in section at Ki^- ^* then 
support a wal^r covered with gold-leaf upon a very 
fine and dry rod of shell lac. Cbarge the woodeo 
ball by holding near It an excited glass tube. While 
it rctoains charged, touch its suKacc with the 5up- 
jiorted frilt wafer, which immediately hold to a very 
delicate cUctromcter ; this will show that the wafer 
bas imbibed loroc of th» electricity from the inrface 
of the ball. A5:nin, pass the ^ilt wafrr quickly and 
neatly to the bottom of one of the boles, withdraw 
it, and upon holding it to the electrometer, no eflect 
will be produced. 

Ss. i,—r/ie Bleclric ITe//. — Place upon aa 
lAectric stool, a metal quart pot, mug, or some 
^er coodacting body nearly of the same form and 
dimension, then tie a short cork ball electrometer, 
that ii two cork balls «U!4peDtlLd on a linen thread, 
to a silken cord. Electrify the mu^, ud hold the 
cSeetromcUr within it, when it will not be at all 
alTrctcd. 

Ej, 5. — InateAd of the electrometer in the last 
(speriment use a mctillic ball, suspended by silk ; 
riKlfify the mu^ and withdraw the ball, it will be 
fpand nut duu-giid hy its contact with the inner 
tttfface of the mug, though it may have been struck 
igslnst its sides many times. 



£r. ft^—Btot, theerh 
eoMbufflnl the afipar»t«- 
coo^sIb of an oral mvial Wj 
aad eovered with twn tmfm. m- 



any 

I ! hi 



I 



eovercd with tio-> 

there bo oo" 
dectiieity. t! ' 

salstiag bandies, be earefnily applied to 
Upoo the reiroral of these cap<, it w ' 
that the whole of the electricity has bee 
frvm the spheroid, io that it will bo 
tbe iDOoK dclicnte electrometer, while fibs 
will be found to bare acquired precisely ' 
quantity ot electricity which had at first 
tbe hall. 

The net t circunstanoe to be obaerred it 
of ao estctided or coatractrd surface la 
apparent a minate qoanrityof eirctricity 
t I fd that the I 

<rct mnU ai!. 
.'• IK. I - ii'jid spread Okci nil cjiiciiuru 

be fo ppparent as if more caiioeiilnfti«l 
cL i i.'i^iir. as in mechanics, themeaaiaiul 
[ ' > the end to be effected, nnJ tlit 

k^ •'* seoMbly a small cootJuctor 

unappmciable on one which is l/ir^cr. Tht 
tricsl intcBsily may be le^. llioutrU the qual 
the same. This is iUtt>-^ 
perlments of Biot, Coot 

Es, 7. — Fii;. 4 reprc*ti..^ .... ..,., 

A, is a stand. R B, two rods of %bu». 
to turn the cylinder of gissa D. E, i» 
of tio-foil, alxiut 2 inches wide and 2 fi 
is a pair of pith bolls connected hy a SCri 
with E. G. is a silk string attached 
elci-lrifying tbe cjiinder, or rather the 
(he balls of the electrofueter divert : 
hold of the iilk thmd. and unrolling the 
lamina from the rrHndrr, the balls gradu. 
lapse, thus indicating a diminution of e 
intensity. Again, winding up the lamina I 
will diverge as at first, making an allowai 
trifling dispersion of the fluid during tb* 
ment. 

JSj*. 8. — Make a number ol pasteboard 
cover them with tin-foil, and suspend ihf 
each other by a metallic thresil, a hanillc 
or a silk conl being attached to tbe uppc 
Let the pbites rest on each otlier, and p 
whole together upon the top of a gold leaf 
meter, electrify them so that the gold Ir 
verge; then gradually draw them up by 
thread at the top, when tlie diverging will i 
in proportion, and again increase when let 
at first. (See Fig. 7.) 

Bjt. 0. — Insulate a metallic cup, or 
Doncare ])iec-e of metal, and place within 
long metallic chain, having a salk thread 
of its ends. To a wire proceeding frotn 
suspend n pith ball electrometer. Then 
the cup by eiving it a spark with a kn 
charged bottle, and the 1yill» of the elec 
will diverge. Lift up one end of Ilie eb«: 
the balls will diverge, let il down again I 
recede as at tirst. 

Kx. 10.— Kxcite a long strp of flannel. 
riband, by rubbing It with tlie fittvvea, thva 
the knuckle to it, take as many spark 
riband a ill give, \nt when the riband o 
hns loat the po«cr of giving any moro m 







doublr or roll it up ; by which open- 
inel ap{»c«r8 to be so stroagly eirctrical ; 
only Kivea sptrlu to the baud brouj^ht 
throws out B[>ontu>eous brushes of light, 
ppMr very beautiful iu thr dark.,^ 
Atticle hu extended ao much fartlier than 
attd, thitt we cannot fatly enter Into the 
Kltvtnrtil ftulurtifm, hat will only cx- 
Fl^rtrt 1. 2, 3, 8, and give the esperi- 
Iting from them, leaving their cxplnnition 
njiportunity. To undembiiid tbc«c 
pren in a cursory decree, it is nei:eisary 
xhni whvn s charged body contes near 
'>'d, it affects the fluid containtMl 
>ly. Bod drives it to a diKlmicf, 
}^ 111 [if;. 1, an electrified bull be bcid 
lou^ conductor furni>hed with clectro- 
rccitUr distances, it will drive away the 
K^ vnd nearrxt to the biill, to that which 
mt, and all the electrumetem except the 
will be clTcL-tcd ; those nearest to the 
dy will; b<* elrcthlii^d minna becaasc tli« 
repelled ; tlie next pair olxo minus, 
leM degree, the ceuln- pair will be un- 
fourth pair will be electrified plus, as 
Ifed a part of the duid from tlie other 
tbe tifth and last pair will be just aa 
r-charged as the first pairwai deficient. 

■Figure 8, bbows how the result may be 

•Pcor^tely ojscertoincd. It represents 

ictor* furnished with electrometers. A 

held fit one end ivill electrify the 

'beo (bus chargcJ, carefully withdraw tlie 

n lien those ut each end will be 

■ ly, the* other Deg-utivcly. Tliis 

Puuiutii^ each to nnoliirr electrometer, 
tbra together, when the divergence 
I cesae, the one conductor ncuLruiiz. 
OUier. 

li, — Fignre 2, shows an electritrid donbler 
d to a i^ld leaf electrometer, if Che char^ 
bleated be too feeble to be detected by the 
irca. it may be made apparent by uYproacb- 
B. which will drive the auMl |>ortiun of 
most disiaiit p'lrt or to the extremities 
leases, wbui it wiU become apparent by 



IS. — Figures represents another electrical 
■p QtUed V'olta'w cotnlrittiHy plattM. Tlie up- 
I* C, is formed of metbl or wood, covered 
furnished with a glans handle. U, 
Ung pint* ; a piece of biikcd wood, 
:hunrd answers well, the latter 
ted dnnng the experiment. A, w a 
»ld leaf tleclromctcr. To use Uiis ap- 
thv pUte C ui>on the plate B, and there 
connected for eianipte with a pointed 
distance iuti> tlie Qln>ob)iUcrc. 
wwe may collect, if uti.icucd 
10 tittle tlaid as to be unAiipreci- 
with this upper plate CI this 
Itrafe the quantity until it bj^eiug 
A, will, by electrical induction Rffect 
the sold leaveii, and render the experi- 



(Tb Ift eotttinhCtl.J 



HORTUS SICCUS; 

OR rBsrAnATioK or arcciUEKs or viXKia. 

(from WUherini/B Bvtany.j 

Many methods have been deviled fur the pro- 
servatiou of plant6 ; v,n shall rehttc onl^ such u 
hare been found moxt sucx^cssful. 

First prepare a press, which a workman may 
make by the following directions : — 

Take iwu planks of well-seasoned wood, sot 
liable to warp. For this purpose none will proro 
more serviceable than elm. The jiUnks slioutd 
be two inches Lliick, eiRhleen inches lonft, twelve 
inches broad. To reflate the dc(^ec uf pressure 
bcruws wcro formerly used, but wod^vs have been 
fuund proforablo, oii more manageable and cffica- 
cacioufi. Provide, tborufore, two wedges of woU- 
scasoued wood, to pass through uprights affixed 
to each end of the lower plank, and risinR through 
the upper one. When a press is not at hand, the 
specimens, may be dried tolerably well between 
the leaves of a lar^ folio book, laying other books 
upon it to give \\ the necessary pressure ; but in 
all cases too much pressure must be avoided. 

Secondly, get a few sheets of strong card paste- 
boudt and half a doxen q\iires of large, sodt 
sponf^ paper : such a.s the statiouet« call blossom 
bloltin; paper, is the most proper. 

The nUuta vou wuh to preserve should bo 
gathered in a dry day. aAcr the sun has cxluiled 
the dew ; taking particular care (o cutlect them 
iu that sLuic wherein their generic and 'Specific 
chiu-acters are most r:uuspicnaus. Carry them 
homo in a tin box, wluch may be made about 
nine inches long, four inches and a half m-ide, and 
one incli and a half deep. Get the box made of 
the thinnest tiiiued iron tital can be procured; 
and let the lid open upon binges. The box should 
be puiutcd, or lackeifJ, to ptovcnl its rusting. 
If any thing happen to prcveul tlioVnnicdiate use 
uf the bpeciniciu you have collected, llicy will be 
kt'pt-fresh two ur ^cc days in this box, much 
better nioji by puiulig them iu water; but the 
blo&aoms of some plants arc so dclicuto* that they 
shrivel und full olf in n, very bhoit time, and 
ufieu before yo\i cun well cxaMiinc tlioni. In 
this case, put the stems in water, cover the wboU 
with a glods bell, like thode used in gnrdons, or 
the receiver of an air-pump will do; expose them 
tv the sun, and iu hull an hour you will Hud tbcm 
ci'mplctcly expanded. When you arc about to 
I>rcficrve tiiem, lay them down upon a pasteboard. 
Oft much 08 po^ible In their natural form ; but at 
the same time with a particular view to their 
generic and specific characters. For this purpose 
it will be advisable to separate one or more of 
the flowers, and to display them so as to show 
the peueric character. If the specific character 
di'j.nid upon thp flower, or upon the root, a par- 
ticular display ol' that will be bkcwi&o necesaary. 
When till' plant islhns disposed upi^n the paste- 
board, cover it wi(b eight or ten layers of the 
blotliK^ paper, and put it into the press. Exert 
only a ^^J^It degree of pressure, for Uiu firel two 
or three day*; then examine it, unfold any 
unnatural plaitn. rectify uiibtakvH, and, nAcr put- 
ling fresh \u\\*vx over it, drive the wedges a lillte 
lighter. In about tbrec days more. sc]>nrnlc the 
plant from the pnstebuard, if it be surtincnlly tirin 
tu aIIuw ul A change of place; put it upon a drv 
fresh poslcbuAid, and, covering it tvuh ftpsli 
blossom paper, let ii lunirtiu in the pre^s n few 
drtys lunger. The pieas sliould stand in the 



1 



d2 



MAGAZINE OF SCIENCE. 



flnnahinc, ur witUiD ihe influence of a Grc. for 
nothing is so ilcilnietiTe lo the beauty of the 
spectmeuB as ii luni; cunliuiied dumpncaa. Shrubs 
and mauy of ihi; harder pcrenniKl plants will lie 
much ueaier in the hvrbarium. if the tiarkof the 
principal stem be slit up with the point of a sharp 
knife, su as to allow the inner wouUy part to be 
extracted. 

When the vpcdmcn is perfectly diy, the usual 
method is to fasten it down with glue, or paste, 
or goiD-wator, on the right hand inner pa^e of a 
sheet uf lar^ strong wxjLiug paper. It requires 
Aooie dexterity lu j^luc the plant neatly down, so 
that none uf the gum or paste may appear to 
defile the paper. Press it gently again for a day 
or two, witii a half sheet of blossom paper between 
the folds of the wrilinp paper. When it is quite 
dry. write upon the left band inner pftRc of the 
paper, tlie name of the plant, the spccilic charac- 
tor; the place where, and the time when It waa 
found ; and any other remnrks you think proper. 
Upon the back of the same page, near the fold of 
tb« paper, write the name of the plaat, and then 
place it in your cabinet. A small quantity of 
finely powdered arsenic, or corrosive sublimate, is 
frequently mixed with the paste or gum-wnler. to 
prevent ilic derofitations o(^ insects ; but the seeda 
of BUvea-acre finely powdered, will answer the 
•anie purpose, without being liable lo corrode or 
to change the color of the more delicAte plants. 
A little alum added to the paste makes it keep 
longer, and a little very coarue brown sugar 
dissolved in tlie gum-wtiter renders it less brittle 
when dry. Some botunists put tlie dried pUnla 
into the sheets of writing paper without fastening 
them down at all. which I think much Uio most 
UBchil way : othera only fasten them by means of 
•mall slips of paper, pasted across the stem or 
brmnc-he«. and others again sew them lo the piipor 
with a needle and fine thread. 

Anotht-r more cxpe'lilious method is to take the 
plautsotii uf Ihe preas. after the Orel or second 
day ; lot th.-iu remain upon iho pasteboard ; cover 
Ihem with five or six leaves of blossom paper, 
and in.ii Uirni with a hot smoothing iron until 
they are p.-rftfclly <lry. If the iron be loo hot it 
will chanRf the colors; but some people, taii?*'^ 
by long prartico. sncce.d Tcr>- happily. This is 
Ihpbwtnii'thod to iti-nt the dillmiit Bpcnes of 
(Irchis and other sUniy nnu'ilagumus I'lauia. 

I nm Indrhtrd to T. Velk^. K.;».|. for the 
following impnivcil ineihod of drying plonw, 
which, being the result of much exi»cficnce. 
oannoi but prov» accepUblo to the practical 
bMUn*»t:— 

M^__ I plum tht< plant, when fresh, between 
tavrial ■ItciMiB I'f blitiiins \u\\wt, and iron It with 

» J- ■ 

ttii 
rti" 

It" 



ami II 

UM'lllO 



Klrongiv woruiLd, 

ii-d. l^ho lluwcrs 

. ... iih gum, upon the 

iiiif to reniikin, lUid iron them 

,. h iiH-ans they become almost 

Im |. i|rr til their proper forma. 

l...n able to llx, which 

'lo ilnwiTH during tlie gradual 

. of •und-htats. and other 

.1.1 boforo irifd. 

iMpiire a more moderate heat 



".Mmtiit phitilii - , . . 

Ihnn iilhi'iti i.*pr(iniio must dotennnic Una. 

^,,,1 t,„„.|„ «l..i« \\w nicely of iha exporuiieuL 

'Ibw |\ n Mild .ulnr* sofcrii to remain mure p«r- 

Ll bf iMd ni"do Ihau l«y any ^'H""" ' .''«^<* 7*» 
Iblr »M liy "-ir Ihr iu«rlla).lnu«. and succulciit 



plants do not succeed 80 well witli rrvnect W 
color, under the hot smoothing iron. I nnve alwayr 
found that they failed full as much . 
preaorved by other means. Th.- 
blossoms in the class Didynainid. 1 lliuij urroi 
fix by a sand-heal. Several of these, m» wtH m 
of the rough-leaved planta, 1 have prcseitil 
tolerably well by ironing. 

" It is necessary to obserre, that in eompoafti 
flow«£8, or in thot« uf a solid and more stobboa 
form, as the Ccntaorea, Ac, some little art mai 
be employed In culling away the under put, tf 
which niuaus llic profile and form of the flowto 
will be more disUnclJy exhibited, provided tli^ 

art lo be pasted down." " Afler all, it mint 

be remembered, Uiat a plant, when preserved hi 
most perfect stntc, is a kind of Hygrometer, tat 
if exposed for any time to a moi5t atmosphere. <r 
laid tip in a situation which is not perfectly i(y|. 
will imbibe a degree of humidity th&t most sooa 
prove injurious to the beauty of the apccimeit. 

Major Velloy sent rac some plants 
these means, which arc the most beaul'iful 
mens I have seen. The facility of dryi 
by ironing must render this uieihod p 
acceptable to the travelling botanist. 

^ 7*0 6e amtamed.J 



dried 



ing 



VARNISHING. 

{Rcgumed from page 'dH.) 

Sundarae Yamish. 

H ox, gum sandorac, 
2 07.. {tounded mastic, 
4 oz clt-iir turjH-ntiibe, 
4 02. jHiunded glaxs^ and 

32 oz. alcohol. 
Mix and dissolve an fwfore. 
Cnmjmund Sundarac Vantiak. 

3 nz. pounded copal of an ainl»r< 
R oz. gum sandarac, 

3 uz. mastic, cleaned, 
3^ o7. clear toriwntine, 

4 oz. pounded gksa, and 
32 oz. pure alcohol. 

Mi.T these ingredi«ats, aad pumie tlie 
method as above. 

This varnish is destined for articles tut 
frictiui), iueh as furniture, chairs, fi 
moulding, &lc., und even metals, (o which iti 
be ujiplied with success. The sondarac 
grtfat durability. 

CamphoratM Sttndarac Vamuh /vr c«t 
M'oriu, Ortstintj Uoxea. tie. 

ho. I. — 6 oz. gum saodarac, 

4 oz. gum elemi, 

1 02. guui anima, 

i OK. camphor, 

4 oz. jMiunded glass, and 

3S OK. ptire alcoliol. 

JMakc the varnish according to the tlirrvtiona 

given. The soft re^in mu»t be pounded with th« 

dry biviies. The camphor is tu be uilded la pieces 

No. 2, — 6 ox. gallipot, or ^^ bite iticensc, 

2oz. gum aninia, 

2oz. gum eleini, 

4 ox pounded glass, and 

33 OK. alcohol. 



MAGAZINE OF SCIENCE. 



53 



thcramiiih ^*ith the precattUoiu Indicated 

icotnponml uirulic v.Tmi»h. 

letwi. Iisi varni'-iioh arc lo ho nscd for ceilings 

. Colored 'tr nnt cnltirctl : titcy roav 

n^eil jw d c^jvurin:,* Ui parts luintcil 

rtuj; color*. 

■ itUfUM Samrfarar VarntJih fnr Waimtrotliitg^ 
U AriirtcM of FumUart^ BaluMtmHts^ and in- 
Hailing. 
i^Sio. t<— 6 ox. f^ara aantUrac, 

3 nz. shell Inc, 

4 oz. colophonitiin, or rcftin, 
4 oz. irhite iclajw pnmlerrd, 
4 or- cl«ar turpentine, and 

33 az. puro alcohfl. 
Ive tlir varnish accnrdin;; tn the diroctiom 
nijmund nin5lif r.inush. 
Ii l«i sulfieieiilly iliirabk* In Ik: applied 
alined til diLily and nmlinual use. 
nslir!* t-otupuxed uiih cofml might, however, 
cAses, lo be preferred. 
"iotortd Vamiih/or Violiiu, and t'thrr slHmjrd 
intmenttt otso far Plum-trw, AJithoffantf^ and 

4 oz. gum sandartu:, 
2 OS. teed \%Cy 
1 oz. mastic, 
1 oz. Benjamin in tears, 
4 oz. pounded tclaita. 
2oz. Venice turiH.>ntiiie, and 
32 oz. pure alcohol. 
[ITbe gum sandarmc and lac render this varnish 
inble ; it ma; be colored with a litUn taOrun or 
4np>D'« bl()iMl, 
fot VitmUS of a ffoUt color. 
8 oz. amber, 
2 oz. ^m Ut', 
8 07.. dryinu: Unseed uil, and 
16 oz. essrncf of tur{)enlinc. 
iHwoIre sejiaratcly the ^nm lac, and tlien odd 
' limber, prepared and pnlvrri'/erj. with the lin- 
oil antl C99ent-c Tcry warm. When the whole 
iluitpart (ifits heat, mix iu relative proportions 
Elart:s or annalto, of terra mcrita, l,'uiii gullte, 
's blood. Thi» rarnish when applied 
metals, gins them a gold color. 
Turjtentine or (iolden VdrHuA, being a 
ml III iji)Ul and dark eolort, 
U'toz. boiled linseed oil, 
8 OZ. Venice turpentine, and 
A oz. Naples yellow. 
;:lbe oil with Uie turjtcntinc ; and mix the 
iiloiK ptilrcrized. 

yello^v i&an Qxide of lead. It is sub- 
|ifaere for rcsinjL, on aevount of its drviuff 
and in particular of its color, woico 
tttat of Kold i atoLt use ia made of the 
in applying f^old leaf. 
»Uow, however, may be ouiittcd when 
of vamififa ia lo be aoUd aod colored 
In this ca»e an ounce of litlurge to 
pound of composition may be sob-stilutcd in 
isteid. without tliia miAturu daiof; any injury 
M the color which is to coOAtitate iJie (^ound. 
Tmnur'M VarniJtft/or Bos Wood^ 
It oz. Rced lav, 
3 oz. guju oandanic, 
1^ oz. Knm elemi. 
2oz. Vt.'uice (urpentinc, 
£ oz. iMiundcd kIj&s and 
2\ »Z. pureulioliol. 
arluu uf ^t. Cluuilt: do not all employ tJn» 
isla, vrhtch required to be corrected on account 



of it5 too (Treat drynen, whieh la here leanoed by 
the turpentine nnd icnm clemL This eoinporitioa 
ii secure from crackim;, which diffi^irva tiiew 
boxes after they hare been used for aomc monllis. 

Nu. 3 — OUicr turners employ the irum lac 
united to a little elcini nnd turpentine difi^ted 
ftome months in pure alcohol exp<t«cd to the nun. 
If thii mcthml befolloweil, it will be proper to 
snbxlitutcfor the samlarat;, the same quaiiuty of 
^iim lao reduced to powder, and not to add the 
tiirifcntine tn the alcohol, which u«i^ht In he 
cxet,*edingly pure, tiU towards Uie end of the 
infusion. 

Solar infusion requires care atul attention. 
Vcawltiof a snfficientaize loallow the ^pirituons 
vajwum to circulate freely ought to be employed, 
becauw it is neceuary that the veurU should be 
closelv shut Without tills precaution the spirits 
wouhl become weakened, and abandon tJic resin 
which they laid hold of durine the first days of 
exposure. This perfect circulation will not ad- 
mit of the vessels being too full. 

In general, the vaminUcs applied lo artieleg 
whieh may tn: put into the lathe acquire a great 
deal of brilli^ucv by polishing ; a pieccof wuullcn 
cloth is Hulticicnt fnr the operation. If turfHrntine 
pretlomiiiatcH too much in these compositious the 
polish does not retain its lustre, because the heat 
of the hands ts capable of softeuin^ the surface of 
the rarnish, and in this state it readily tarnUhes 

To Varnish Drctting /Joxcj.— The uiost of spirit 
of wine varnishes are destined fur covering pr^ 
limioary preparations, which have a certain decree 
of lustre. They consist of oemeut, cohired or not 
colored, chargi!d with landscapes and figures out 
out in paper, which prfxlnccA an effect under th« 
transparenl rarntsh : moat of the dressing boxM, 
and other small articles uf the same kind, an 
covered with this particular composiiion. wjiich, 
in general, consists of three or futir cuutings of 
Spanish white pounded in water, aiid mi\^ up 
with parchmentglue. The first coating issiuuulhed 
with pumice-stoDC, and then polished with a 
piece of new liueu and water. The roatJug in 
this state is fit to receire the destined color, after 
it has been ground with water, and mixed with 
parchment glue diluted with water. The cut 
figures with which it ia to be cmbellislied, are 
then applied, and a coating of gum, or 6sh-gluc 
is spread over lliem, to prevent itie voniish Irom 
[tcnctrating to the preparation, aud from spuihng 
the figures. The operation is finished by applying 
three or four coatings of varnish, which, when 
dry, arc polished with tripoli and water, by uu;a,ns 
of a juece uf cloth. A lustre is then given to the 
surface with starch and a bit of doe-skin, or very 
soft cloth. 

(To tm continued.) 



DURABILITY OF STONE. 

Tiic Report recently made to the Coiumi.ssioaers 
of her Majesty's Ireasury, by Messrs. Harry, 
De La Dechc, W. Smith, and Charles H. Smith, 
oil the Sund.stimcs, Limestones, uod Oolites of 
Britain, forms, with the numerous tables and 
results uf experiments by Messr>. Oauirll uud 
Whcat^tooe appended to it, one of the most 
valuable cuntrtbiitiuns to architectural science 
Uiat lias been made iu modem times. Due hun- 
dred aud thru quarries aro descnbvd, oiuety-six 



« 



I 



MAGAZINE OF SCIENCE. 



^ 



bnildingt in England refenvd tn, many clicmical 
anftljrsia of the fttnncx n^vcn, and a. (pvat nnnibcr 
of cxperiiDpnU related, showing, iLaion;; oUi«rr 
pomiA, lilt: LMiIioaive {wwrr of eat-h stnue, and tbe 
Ainoimtorditiotcgntioa apparent, when subjected 
to Brmrd'f nroeeta. 

Of this dcK uinent wc bare only space tn quote 
tlie foIloMfing: — 

" Of tJie nrcenity aod importance of the in- 
quiry u)w>n which wc have l»eon eui^a^'il, the 
lamcntuhlc rftccts of tlcc<>inp*isiUyn <ibK.Tvable 
in the f^rrtilrr partof the linii'stone tiupltiyt-d at 
Oxford, ill thf inuj^ncsiau liinctont- of the Mins- 
ter, chun hen, and other puhlu' bnildinfp nt York, 
and in the ^ud!)t(ines of wliirh the churches aud 
utlicr public buildiuf^H in Derby and NewcA5tlc arc 
nouMructed, afTunl, aninni* iimntTous other ex- 
aoiples incunlestahtr and !<triktn^ evidence- Tlu.* 
unequal ftate of preservation of many buildings, 
often priKJucc'd by the varied ipialilv of tite tlone 
cmplojed in ibem. ultliuugh it may hare liecn 
taken from the same quarry, shows the projwiety 
uf a minute examination of the quarries them- 
aelvea, in order to acquire a prtiper knnuled[(c uf 
tbe ]Mirticular bcd» from wlienro tbe diiTc'rent 
atones have been obtained]. An iiitpiclioa uf 
qnarriea is also desirable for the purpo«e of 
aacettainiufc their p<>wcr of supply, the probable 
extent of an^ given l>ed. and many other maltcra 
of pmclieiil inijMtfinorr 

•'Ilfivi tliat the best stone in 

quar^ic^ i i*t imly in [»art workcil, 

in»m tbi: t..~i .-I ........^ ,..nl rcmoiin^ those beds 

with which it may Iks ansoeiated, and, in ooi^ 
fc(jnencc, the infrrinr material i% in cuch cases 
MUppltrd, especially when a Urve snpplv is 
rrquirc<l in a shiirl K[uire of time and at an 
ijficiciit price, which is often the case with 
trsjwcl 111 wiirk* undcrlakcn by cuiilract. 

•i ^> .,., ■'-.. Mimical supply olAIom- iii pirtieiilar 
lo« .^ i| urien ap|>eur In tlr|iciiJ on ai:~ 

*i(i' ' iintauccs, sutb as the oHtof qunrr\- 

iuK, ihc lUxiec of facility iu tran«[>orl, and tbe 
prejudice that ernerally exiiti in favour of a 

kteriul which hiislic-en'luug in um? ; auti as ibo 
ms of iriiU)i[Hjrt have of late _\car» been t^reatly 
'Bscd, It Ik-coiiks CMsrnlial touM>eitalii whether 
better materials than tli<i«e which have been 
cOlplo'Vei] in any t^ivcn phice may not be ubtainetl 
froinodier, altlnpuKh more dl&tant, U>calilic% upon 
i'^|unlW gulvunliivM'iiitB irrm«. 

eui] 

Ih^i ; ;., . d 

mcctiuiitral (nlllJHton^ io ^\:Ml■l| «u<'b I'luiiva arv 

rupKid A> fiw'iiTilt ii><- ^iii'lrttiiMt that arr 

UMi . il for ftuch pur|H)fes. and which 

i>mf>n*i.'c] of either qiurtK «r siliti- 

' i''d b) slliciouA, ;ii 

' ' '■■■''■ uiattiT. Oieir il- - 




indr- 

. ur the ciubuutttr» ol lin>« 

UMirly pure or mtKcd wiili 

■ > ir de- 

cquaK 



I iruiu 



I iiitkr loruiation. 
niurr cipcci^lly 



when micaceous, theplati'aof miralwiaap 
de|KKitcd in pluncs )»ar»llrl to th*»ir brda. Hvarr, 
if such stone be phirt^l " ' ■ xk 'w\A t« 

plancsof buunrilion in a itkia. il «iH 

decompose in Ihikesacf iHiin.K y„ i,„r- lUfikava W 
the lamina*, whereas, if it be placed m* iWi O* 
planes of laminatimi be boriiuinLal, thai iav ■'<' 
commonly u|K>n its nalnml bed, the aBKMiaS J 
decuni position will be comftarativelj iaiaalcilaL 

" l.imeslnncs, such at tc&al aa al« Wlially i^ 
ployed f<ir building purposes ai» wK litkh Is tti 
kind of lamination obwrrnble in nodsftoKii 
nevertheless turielicf exist, rt]>ectallT th«ae n^ 
roouly tcrmeil "shelly." ulii. h b'isi 
laminatetl strueturo. gru -.Llrl In 

planes of their beds,, m th« ■ 

prccaation in placin. 
that the planer nf I. 
necessary as w I ih l : . 

"'Iht vtuietici ' 
being comjKwed of ■ 
calcareous matter u( tAfuil < 
ncccasitv, suOcr unequal det" 
such ovifonn bodies r.iid tl-c • < 
coherent and of the same chtm 
'I he limestones which an- m»'> i > 
from Wing formed of < 
fossil shells, rcuu'Uted by • 
decomposition In au unequal ui>itiit''r. in 
BtHpicnceof tb« ftbclK which, bciiiie r«f«^th*i 
part trysuUine. oBcr the neatest 
resistance to thtt dccoupeslaf eOei U ii 
atmo>pht!re. 

**'niu cHecU of the chemical and 
causes of the ilccompositiim of stoor In 
are found lo be ^reatU mtuhfled 
such buiUliuf^s mat bt uttuotc ID town 
The state of tlie uluio^phcrc in snuky 
pulous towns prti(Iuc(.-s a i^rcater 
composition iu buibUugs hi •''< 
■.imditiuns Wini; ctpul, than l 
the oj»cn country, where msii 
ptixlucts which arise fnnn sii 
injurious to huildintrs, are ruit i 

'■ The clicuiical uctuMi ul 

firudnces a change in the cntir t.n.r 
imcstoacs, and iu the crin- "'^ 
sandstones, Bccorilini; t't 
exposed to it The tw 
atraiisphcric eanscs occasions viib^T a i«ta>»»i «* 
disruption of tl» exposed jiarliclrj ; tW ^*^ 
b( means of tviwerful winda ami ctiivfeM 
and tlte latter b) the ciinf;el itioo of «liV^ 
iuiii, or absorbed by the #•■»!. rn^l pnrtii«f 
•tone. Tiicse effects L 

action rrndcnnm lite «t" i . tu W 
easily afl'cctcd by chrmiciii •t.Uuu, wkkft 
hx inn»l;intU [irr«rutlui{ UcW surfoCrS, 
. Ifoetsof ibcfc 
1 « elimatc are 

;. ■ ..f 

II . -l 

ar; , ■ .""- 

and (aiu* lioui ii" 
sirahle that stones 
Icavt be vinpliit < I m : 
" Ituildini;^ . >i 

iHMSCSt a UTC.l* 

and suioky tt< 

they alujiMt > 

aituaUous, and wbKh, 

uTcr their rntirv siufacss •■*& ^ sxctxisi 

ti-etive ioflucbcc sipuoBAlM v t i tu m m 

<krum|Kiaitian of tbe stone tt]MO vwrii 




r,^ wiui •acii 

:) the CTMiatrv 
uTrr t^am m 
to lirlwi, »u 

Ue«ame w^xn^ la 

wties flnnly 



MAGAZINE OF S« 



anin^lttiice of Iho rlifflTfurc in drprce of 

lity in the rame malpriul siiUjcrUsl to tho 

or the atmo<;[ilierc in tnxvn uikI cmintry, 

may notice the several fln^ta of cnhiiuiis and 

t'.T hhici.* or sionc thot were quftrnod at the 

.u of till! crecucin of St. I'liul'* Cathedral in 

mlnti, tiKd whltli are nnw Iving in the island of 

rtbutd, near the quarries from whence they 

re oltlainud. The bltiekit are invuriahly foiiud 

»e covered with lithi-tis and allli>tui^h they hare 

iin ptpoKcd In all lite Tici^situdi'i^ i*f a marine 

' . fnr mnrc than I.'jO vear.t, they still 

M?Jitli llic lirbcm llifir uriifiiuil form, 

■.'..V niar1(>( u( the chiael eniploved ujHin 

an, whilit the ^mnc which wi« taken Irom the 

DO qnarries (selected nn dmibt with eijrul if 

t unater eifc than ihtf Mocks nlltuletl to), ami 

lord ill the cathedral itwll', is, in those |MrtB 

' ■--■-' fipiMwd to the south nnd sonth-wcst 

i:d in Aomeio^taiUTS tu he fii<t inoiilder- 

1- rtf ini>rc imprtrtioee in the si^leetinn 

(•rahullrttttg to l>c Bilnaic in a pn[/iiloi]s 

■A )iUi4>Lv Uiwii thnii for one to Ik* placL'd in an 

Itn connlfY, where all cdiBces nsimlly hecoiiie 

' i* above Mated, with lichen*; for 

.1 sncli town* thow fronts which are 

.-:._, , 1 tu the prcvfiilinij winds and niin.s will 

■L became blackened, the remainder of the 

PBn^ will con^antlyethihtt a tint depending; 

pan ifie naturU color nf the raateri;d einpU>ycd." 

h thmiM be itatcd that the object of the above 

irntiffntbm was ihe selection of 4inne for huild- 

V the HoiHM of Parliament, and the Report 

■ ' ' f. "'.iW*:— 

I, having weighed to the best nf 

...L- evidence in lavour of the varinnt 

i.ncs uhieli have been hroui(hl umler 

ration, and frcoly admitting that many 

14 well ax liiueitonits pos««9 very grent 

~ ts hnildin^ matcriuK wo feel hound to 

inr durnbility, as instanced in Southwell 

■ ■, and the rcnulla of oK]wriincntt, as 

1 lie nccumpanving^ tables ; for crystalline 

'•initiined with a close approach tt» the 

proportions of cftrbonatc of lime und 

• if miignesta ; for uniformity of stnic- 

ny and eronoiny in conversion; and 

' r. the tnagneiiiitu limestone, 

r Moor and its neitrhhour- 

.. , .,..i)u, the mnA fit und proper 

■' be employed ia the proiwsed new 

1 Porliaiuent." 



PREPARATION OP CATGUT. 

wo make known the preparation of the 
iM of ahecp, fur the manufacture of various 
[of eords. we ahali mention that of those 
)r Uio horse, mule, or asa, called LorrainM, 
•^aiida. 

, polishera, and various nthcr mechanics, 

If cords, m:\rmf(u:tured from the in* 

le horse, &e , freed from the mucous 

The pit is token hold of by one 

•vhirh is (liruvt a wooden ball, fastened 

' stake, fixed in a block; below 

cutlinR-blades; or, to render the 

■ ..M.re cletur, Jt U ft cutter formed of 

: uiLd-sunnomitcd by a wooden hall: 



they draw down the intestine equally over these 
blades, with both hands, so as tu cut it into four 
equRl strips. Thejr take four, »ix, or eight, of 
these strips, accordingly as tho^ wish the cord tu 
bo thicker or thinner ; then tie those auiiis by u. 
particular kind of knot at one end, witli larfzc 
twine, made on purpose, which tliey call a lace; 
and pass the end of it over a peg^ secured in & 
hole made in a post stcun);!y fixed : at the dis- 
tance of about 30 feet, ia placed another post 
with pcpn, on one of which they pass these stnps: 
near to tho first post, the strips are all tied to];clhcr 
with a new IftLc. which ihcy fasten to the pc(C 
whereof we have just spoken : the workmen call 
this -first operation the " warping." Thoy cat 
these strips, aud fasten iJiem as above described, if 
they arc lunp enough (wliich is generally tho CASe,) 
being careful lh.it the end:) are always Uiken iu 
with the thread. havinR cut them previously 
across, so that the Bc.ini shall not form any unequal 
thickuesa. If iher are long enoujjh. tlicy make a 
a second length, till the gut ia oU taken in, or tUo 
pegs entirely filled. 

When the wefl is finished, the workman phiecs 
his wheels conveniently, and passes over the hook 
of the part the thread which holds the wuA- 
curd : ho puts on a serond laee, if the wheel be 
strong enough to bear it; rIvos seveml turn* to 
the wheel by means of a handle; and places the 
already-twisted cord over a hook. Ho acta tho 
same with every woven cord; passioi; his hand 
carefully alunK the cord from i!ie wheel, aud 
cuttin;? with his knife all thnse fibres >>r threads 
which will not fonri one body with ihe cord. 
This never shortens in dryint:, provided it is 
always gathered toKcUicr nt the same dimension 
over tlic pegs. Some hours having eUpsed, they 
replace the cords ujion the wheel, and twist ihctn 
afresh : 12 or 15 hours afterwards tlicy lake them 
one after the other, and fasten the lai-e to a pi«g 
wliirh they turn with the haml; the wheel seldom 
being strong enou;:li. This twisting beinti; clfccted, 
they rub it witii a horso-hair eonl dipped in water, 
which they form into a bundle, and hold between 
their hands. This operation ia called *' slrotching." 
AnoUicr twisting is made three liours afterwards; 
and they stretch it as forcibly as possible, alter 
Again fixing the cords over tlic pegs, and to the 
posts. 

If the cord, when sufiicicntly dry and twisted, 
is not exactly even, tliey polish it with a piece of 
dog-fiflh skin ; but if the horse-hair cord has been 
passed enough over it. thai becomes unnecessary. 
When tho cord is ilried and stretched, it is 
generally sulphured. When perfectly dry. they 
cut the two ends near to tho lace, and coil it iuto 
a ring for sale. 

The instant that the workman who mokoa Uiew 
cords receives the tntostinea, ho is obliged to wash 
Uiem; to turn tliem insidi'-out ; and to stoop 
them in a barrel, containiuf; two puiLs of water, 
mixed with a pound of pearlash. On tho morrow, 
he separates the mucous membrane, by the or- 
dinary means ; washes the guts in a largo tub of 
water ; cuts ihcm into strips ; puts the laees round 
them diirinp ihe day. imd gives thorn tho flrst 
iwtfil : the next day, he finishes them. 

U the cords be not aulllciently dry by the next 
day, he is oblii^ed, for the sake of salubniy, to 
repeat the operations. After this, the fa'lid odour 
ia no longer peroeptiblo, and he may finiah Xht 
cords at leisure. 

Cntfful far Rncketi or BaUledares, —Tlio in- 
testines of sheep, after they have been aicept-d in 



THE 



MAGAZINE OF SCIENCE, 

^na sittfooi of ^m: 



No. LX.] SATURDAY, MAY 23, 1840. [Prick IJrf. 



THE UNNEAN CLASSES. 



I y ^ ^^ f ^ 





3. 







%t 



10 11 12 13 U 15 16 



^^ *W 



1% ^ h^^ \U 



' 17 18 10 20 21 22 23 24 



THE LINNEAN ORDERS. 
Applied to the firut T^rteen Cia»»et, 



W^^ ^^"^ ^ ^ i§ 



Applied to Clans Fourfeen, Applied to CIm» Fifteen. 

Applied to CUux Sixteen, Applied to Clan SeventeeH. Applied to CImm Eighteen, 

Applied to' daw Nineteen. 

^ ^f §if ^f tJ 

AppKed /« C7fl«f Tireutj/. Applied to Claxt 'JVeuty-one. Applied t.t C/axM Twenty -three. 

Applied to Vlfut Twenty -ivo. 

THE ARTIFICIAL SYSTEM OF BOTANY. 

TOL. IX. 



MAGAZINE OF SCIENCE. 



59 



TABLE OF THE CLASSES. 

intM in this diriaioa and the next have alt their stamens of the lame length, and distinct 

from each Other.) 



l(U«AKOBIA .. 
tANUKIA ... 
TaiANDfltA ., 
TcTftAXDILlA . 

Fkntandrm . . 

tliXANDVIA . 



Chanrter. 

Flowers with I sUmen, 
Flowtrs frith 2 stamens. 
Flowers with 3 staintiis. 
Flowers with 4 stamtus. 
Flowcnt with h ataiiieiu. 
Flowen with 6 scameoB. 



ic« 



Nunw, 



7-. Hepta.ndria .. 

8.. OCTA>fDRlA 

9. . Enxcanobia . 
10. . Urcandhia .. 

11. .DODKCANOaiA 



Character. 

Flowers with 7 stamens. 
Flowers with H sUnunu. 
Flowers with 9 stameaa. 
Fiowers with lU sX 
Flowers with 12 &lAmeiM. 



IcottAyoaiA monr than 12 stamens, placed upon the calr^. 

PoLTANDEiA more than 12 stamens, pLkced upon the receptacle. 

OiDTMAMiA Four dtstinct stamens, 2 long and 2 short. 

TsTaADY^iAMiA .... Slx distinct stamens, 4 long and 2 short. 

•MoNODELrniA .... Stamens anited in 1 handle by their filaments. 

DiADKLt'MiA Sumeux united tii 2 bundles by tlieir tiloments. 

CoLYADKLPiif A .... Staiuuns unitc<l in many biindle-s by their filaments. 

SirxoEXERrA Stnmens imitrd by their anthers, distinct from the style. 

GTVAifDRiA Stamens united to the style. 

MoKOKCiA StameoB and pistils in different flowers on the same plants. 

DtUECJA SCaroons and pistils in diffcrcinl flowers iipuu diS'ercnt plants. 

PoLYGAaciA.. .... .. Some flowers with stamens and pistils, others with stamens only. 

CKTTToaAMiA .... Planta without flowers. 



NAMES OF ORDERS APPLIED TO THE FIRST THIRTEEN CLASSES. 



tOGVNiA Flowers with 1 style. 

Flowers nilh 2 styles. 

r«lA Flowers with 3 styles. 

LVYKIA Flowers with i styles. 

rAsrNiA Flowers with 5 tktyles. 



Hexaoynia Flowers with G styles. 

Ueptagy.'^u Flowers with 7 styles. 

Dkcauynia Flowers with 10 styles. 

DoDKCAcvNiA Flowers with 12 styles. 

PoLYCTWtA Flowers with many styles. 



APPLIED TO CLASS FOURTEEN. 
Seed apparently naked. | Ahoiospskmia. 



Seeds in a ca]>sul«. 



APPLIED TO CLASS FIFTEEN. 
Seeds in a short pod. | SiuatiosA. 



Reedi in a long pod. 



APPLIED TO CLASS NINETEEN. 

Poi-TGAMiA yEauALis. All ihc floFCts perfect, or with stamens and stylen. 
Por.vcAMiA SuvEKFLUA. Imier florets perfect) outer witli styles only. 
PoLVGAMiA FauaTANEA. Inner florcLji pcrfecl, outer without gtyles. 
FoLYGAUiA NscBsaAaiA. Inner florets with stamens, outer with styles only. 
POLTOAsriA SaoaKGATA. Flowers collected Into beads, each with a separate involacre. 

i3e in All the other classes, that is, in the 16, 17. IB, 20, 22, and 33, the stamens not boing 

to tell the clanet, they are used as marks of the orders, with the s&me namea as the classes 

!■ — thus, here Monandria means the first order, but before it meant the first class. 

may oppenr puzzling, and really it in so to those who use numbers and not nnmcs; and the 

is strongly recommended not to use numbers for the classes and orders, for these mean 

bat the Greek names of them signify the same in all situations ; and, moreoveri express 

itancc relating to the plant. 

iple, if we Hpeak of a pKint of the 14 th claxa and 1st order, we are not reminded of uiy- 
ig it ; but if we spenk of it as belongiii;; tn ctns^ Didynsinm, and ordrr f^ymnnspcrniiA, W| 
'there are in it two long and two short stamens, and that the aeeds are not in a oipoulc ; for 
signify as much. Again, 

The tliird order of class 3 is Thigyma, and hiu* three styles. 
The third order of clufs 4 is Tei'Ragynia, and bus four styles. 
The third order of dasa 12 is Polvgynia, and has many styles. 
The tliird order of class 13 is Huxa^I^ia, and luia six styles. 

finj that such or jiuch a flower U of the 3rd order, means nothing, for it may hnre 3, 4, fl, or 
but to say it belongs to order Trigyiiirt, or Tetrugynia, inc., uhuwE. at once partly the nsiurc 
il belong to Trigynia it must have throe styles, and if to Tetrugynia it must hare i btylc), and 
the others, 



60 



MAGAZINE OF SCIENCE. 



CHKMICAL ELEMENTS. 

STDROORN. 

(Rfwrn^Jrom parjt 29, and conrlutM.) 
i5x.23. — 7>?;mri^//yrfroyrt,— The|pi»otft*ined 
by the furmer expehinent^ u never perfectly pure. 
TVd retuler it lo, and which ii neccMary fur drlicato 
esperluieats, it must be pajsed throagh a tolutiua 
of potass, tlien ilried by pasting it thrmigh a tube 
containia^ frapncntB of fuicd chloride of calcium, 
(muriiitr of lime.) The bjdrogen procured by the 
deed m position of water hj galraniim ia considered 
perfcrtly pure. 

iU. 2\.—LightM»* nf tfip GoM.—YiM a Jar with 
hydrogen, and let it stand for a few momenta with 
its open mouth upwards, and letting down a taper 
into it, tlic %n» wtll be found to hare escaped. Put 
another jar filled with its mouth downwards, the 
gas will now remain much lunj^er than bfforc, being^ 
prevented from escaping by the bottom and sidea of 
the void. 

Rr. 25. — ProTidfl an air jar with a stop cock and 
jet, and fill it with hydrogen, upon the shelf of the 
pneumatic trough, then set iire to the gas at the 
jet, and whilst it is there burning, slowly lift the jar 
out of the water, holding it by the braaa cap. The 
llame will continue for some time at the jet, the 
hydrogen being propelled throagh it by its Hght- 
ncas, but when tlie sir becomes mixed in such pro- 
portions with the gas as to foroi an explosive 
ittilture, tlir tiame recedes through the jet, and 
llu whole kindles suddenly. 

S'olr. — T^ic jar sltould be very long and narrow. 
/?x. 2G. — Shmrn Ay a Balloon. — Procare a small 
balloon, msdo of the craw of a turkey, or of golU- 
bratrnt' fJiini and fill It with hydrugen ; tie tlie 
mouth and let it escape, it will soon mnuiit to the 
K of the room, or If iu the open air fly out of 
Imnicdintely. 

. '11 . — Trttilmfy nf Oxygm and Hydntgm to 
unite tHtehaniealtif. — Fdl a botiie with oxygen and 
put it un a tube, furnish It with o curk and a long 
tube rnnuing through it; lo the upper cud of the 
tnbe foBtcn by a second cork, a iKittle of hydrogen 
with its mouth dowawartls. Notwithstanding their 
rclaliTc position, after a time they will be found 
wilted t(>i;c!hrr, liidf of the hydrofen having d«- 
aoandrtl to tlir lown bottle, and half the oxygen 
aacf-r- '■ ' ' "pply its place. Hw miztare may be 
abo^ (ken ptaec by exploding the con- 

tatiL^ ' .'tiiT. 

Rr. iii, — yitrtttnthn nf Water. — While hydrogen 
gaa is burning in a jet, hoUJ over the flame a hell 
glass. In I minitic nr two tlte inside will be covered 
with watrr. sriiing frr^m the noion of the hydrogm 
whi ^ ' ■:, and the aiygvn which it rob* tke 

air comboatloo,— When Ae gtaaa bc- 

rumw ...- n^kirr ia BO longer aeen. beeaoaa 

though fnrnird oi btfore, yel tb« heated glaa* dissi. 
putes II In itnam — hence the necessity of a chiouity 
lo rvcry gsa Uxht, tlir frc«]urnt though not the ofdy 
enn»e of the doudiuras of chop wiinluws is the 
irtaBar flttw and the caose uf mtlrry and Iron- 
gDodi beniwning so often rusty. ^M mom 
aCpcl take* plaea la the bwnini of oawUaa Umngh 
M la degree. 

Xr. S9,—Att0mAtithr JCryrAwwn.— Pnta ipov- 
ful of water into a strong soda water bottle, fullt 
with hTilm^n rwii pnrtt. ind fT;;rrj uue part, 
iJ ' caatioaaly 

<:ooohe»tba 
It %i.i uut*i luio name, ana nre tbenfaed 




tim^ 



gases. It is adviaable tbit t)ie huttiv sr 
wrapped In a cloth to prevent (Ian^< 
bottle barrt which La not unlikely. 

Rx. 30. — The mirtd Gasr< inji^att ly JSPuJi*. 
ci/y. — Blow some soap hubblea widk a autlaia if 
oxygen and hydrogen contained in a UaAUf* i^A 
separated and flying upwnrds. oomoaaiteiia laliiM 
an electric spark, ihey will burst with a laaA mk^ 

Hang to the ceiling a bladder 
gases mixed togetlkcr, poaa an 
through it, and a deafanng exploring wUI 
consequence. 

fix. 31.— 7iierT«e tff Bmik 
Procure a thick glass tnbe at lea 
furnished near one end with tha 
wires, and also with a stop code tp 
gssea — let there be alto a ping or 
of an easy motion np and down the tutae, 
ao ai to be air-tight ; exhaust the tuba of i 
past! into it one portion of oxygen atul twatf I 
drogen. The moTeable piston will ntn eta 
gases — these are to be deCooated by Cba < 
spark, and at the moment of dotmrttoi ik»\ 
will be driTen along the tube abo«t \h 
distant from the closed end as at Arat, 
lowance for friction, arising from iha «i 
piston and Its nibbing against the taW. IWl 
instant, as tbe gases are condensed Inta 
piston will be driven back again ipbtc ta 
the tube, by the external pressars of the 
phere. — This tube if gradoated, la 
conrenient udiomotcr or apparatus for tke 
experiments : 

B*. 32.— rem^MwC/HM y W»iPr 
into tbe tube ur rudiomftvr two mfak 
hydrogen, and one of oxygen — npon 
s|i«rk the two gaascs will exactly neat 
i»tlier ; no trace of cither gas wiU ba 
piston will return exactly to the plaea It < 
fore the gosca were ejeotod i 
experiment repeated several 
certain accurately the result, tbe 
it will be found weighs procisaly tW antf 
united weights of both portions of tha gma 
Kj; 3.1. — Hytiroyen Hntiee an/A OsfyMi 
« c^tain rntiti. — Pass into the lube, hM 
inches of hydrogen, and two of 
mtWing tiir t-xplosioo one portkm ofi 

led, as will \tc seen bt the poaitieft of~ 

To prove which paaa two other TolanMiaf] 

gen, and cxplodie. they wiU nnito ami 4v 

return to jta ttrst situation, showing 

has b«m oondensnl into wster. 
Br. ^4.— Paas as before two 

gstt, and flTo of ataoqpherio all 

charga and icsplosion will take ylawk 

maaaaiaa of gas uacMif 

properly wiU wf^iid lo be wfaoH] 

thus ; tbe atmospheric air ea 

gen and i<5titH nitrogen InlUi 

part oxygen, Ira^ra it to units with t 

hydrogen to (ona water, leaving iIm 
Rr. 35.— Porer </ Ormhmthm 

in the tnbe as before, one poitioa «f hj 

IS of air. or also widi 1& of oayfta. 

the apark bo passed through tha mIi 

ston will roaao— ao also If tha q^aagfi^ «f ] 

be increased to 1 1 to I of Ite axfttm^ 

mJxtnrr hr In rrlitiva an4 proftar 

if.- <.-«lts ~ 

till' :ic nr< 

take plaice. 



Dlirni 
itaUa 



MAGAZINE OF SCIENCE. 



r — (jLry/m and tfydrvpen vmiU tiy pru- 

; m coodcDBuig fyriogo barlDg a doied 
it 14 L-aU«il '* the pneumatic tinder box," 
lure of two purts of byih-ogca auil one of 
Dil ttpOQ compresBioK dowa tho piston 
mty. the gwes will unite and explode — 

before water. 

iwUy baa; g;i*ea m liogtUar uutnnce of co- 

indaciog chetnicAl combiuation, Ijj the 

experiment, which seenifl to be nearly 

(ttscoTcry made bj M. Doeberclner, 

€ the BponCaneoaa combustion of spongy 

posed to a atrcam of hydroj^n gna mixed 

jur. A plate of platina, with ex- 

m RrfuM, when plunged into oxygen 

^m gw* mixed in the pmportion which 

in the conititntion of water, caasea the 

•mbine, and water to be formed, the pU- 

ome red-hot, and at laat an exploaion to 

i the only fonditioos neceaaary for tliii 

Bpenmeot being e-xcessive purity iu Che 

in the Biirfacc of tin- plate. A aullicicnlly 

dlic surface can only bo obtained by ifiS- 

Be pUtina to rery stronc; hot sulphuric 

then washing it in distilled water, or by 

the pDsitiTe pole of a pile in dilute' sul- 

Pd. It appears that the force of cohesion. 

<he) force of affinity, exerted by [mrticlea 

I ezbenda to all the particles within a very 

oe. Hence the plattua while drawiug 

s of the two gases towards its surface, 

oobeiive attraction, brings them so near 

^er, that they come witliin the splicre of 

al affinity, and a chomical combination 

Dr. Paraday attributes thu effect, in 

to a dimuiutiou iu the elasticity of the 

articles, on their side* adjacent to the 

id to tbdr perfect niixtare or aaAoviatioa» 

1^ t« »t.- ' ositive action of the metnl in 

D. uftt its surface by ita attractive 

tjt ; -(, when chemically united, run 

ffuce ol the metal, in the form of water, 

vitation. or pass away aa aqueous va- 

ke way for othen. 



IVORY PAPER. 

vUeti which render ivory ao desirable a 
1^ miniature painter, and other artists, 
ersaocsc and nnencss of its grain, ita 
Q water colors laid on its surface to be 
it with a soft wet brush, and tlic fiirility 
tlu: artist may scrape off the color from 
part, by nieaos of the point of a 
^ther cnnvpniRiit instrument, and thus 
isd add brillitincy to the lights in his 
■« expeditiously and et&caciously than 
in any other way. 
pctiooa to ivory are, its high price, the 
ty of obtoiniu^ pUles exceeding very 
limensions ; and tlie coarjcncss of grun 
of these ; its liability, when thin, to 
of the weather, and its property 
jellow by long exposure to the light, 
oil which it contains. 

on the aiirfacA of this paper by a 

cU are much easier cEiHced by 

than from common dnmiiji; 

matanoe, together with the ex- 

UnM which its bard and even surface 



I is capable of receiTtng, peculiarly adapts it for the 
I reception of the most delicate kind of pencil 
druwing and outlines. The colors Inid upon U 
have a j^realer brilliancy than when laid upon ivory, 
owing to the stiperior whiteness of the ground. 
Colors on ivory are apt to be injured by the 
transudation of the nnimal oil. a defect which the 
I ivory paper is free from. The following is tha 
process given by Mr. iCinsUe (of Stretton Ground, 
Westminster) to the Society of Arts, for wliich he 
wns voted tlie sum of thirty f^inea*. 

"Take a quarter of a pound of clean parchment 
I cuttings, and put them into n two-quart pan, with 
I nea^y as much water as it will hold ; boil tho 
mixluro geatly for foor or five hours, adding water 
from time to time, to supply the place of that 
driven off by evaporation ; then carefully strain 
the liquor from the dregs through a cloth, and 
when cold it will form a strong jelly, which may be 
called size (No. 1.) 

" Return the dregs of the preceding process into 
the pan, liU it with water, and a^iu boil it aa 
before for four' or five hours; then strain off the 
bqoor, and call it sute (No. 2.) 

** Take three sheets of drawing paper (ootsides 
will answer the purpose perfectly well, and bcii^ 
much cheaper are therefore to be preferred,) wet 
them on both sides with a soft sponge dipped ia 
water, and pute them together with the sixe (No. 2.) 
While they are still wet, lay them on a table, and 
place them upon a smooth slab of writing ilate, of 
a size iiomewhat smaller than the paper, turn up 
the edges of the paper, and paste them on the 
back of the slate, and then allow the paper to dry 
gradually. Wet, oa before, three more sheets of 
the some kind of paper, and paste them on (he 
others, one at a time ; out off with a knife what 
projects beyond the cdg^s of the slate, and when 
the whole has become perfectly dry, wrap a small 
piece of alate in coarse sand-paper, and with this 
rubber make the surface of the paper quite even 
and smoodi. Then pa3t« on ao inside sheet, wliidi 
ranst he quite frte from spots or dirt of any kind ; 
cut off the projecting cd^gea as before, and when 
dry, rub it with fine glass-paper, which will prodaeo 
a perfectly smooth surface. Now take half a pint 
of the size (No. 1.) melt it with a gentle heat, and 
then stir into it three table-spoons^ of fine phuter 
of Paris; when the mixture is completed, pour tt 
out on the paper, and with a soft wet sponge 
distribute it as evenly as possible over the sur- 
face. Then allow the snrfoce to dry slowly, and 
rub it again with fine glass-paper. Lutly, tike a 
few spoonsful of tbe sixe (No. 1.) and mix it with 
three-fourths its quantity of water ; unite the two 
by a gentle heat, and when the mofis has cooled, so 
as to be in a semi-gelatinous state, pour one-third of 
it on the surface of the paper, and spread it evenly 
with tlie sponge ; when this bos dried, pour oa 
another portion, and afterwards the remainder ( 
when the whole has again bocome dry, rub it over 
lightly with fine glass-paper, and the process is 
completed; it may, accordingly, be cut away from 
the slob of slate, and ii ready for use.*' 

The quantity of ingredients above-mentioned is 
sufficient for a piece of paper \7\ by Ib^ inches. 

Plaster of Paris givts a perfectly white surface ; 
oxide of cine, mixed with plaster of Paris, in the 
proportion of four parts of the former to throe of 
the latter, gives a lint very nearly resembling ivory ; 
precipitated carbonate of burytca ^vtis a tint in- 
termediate between the two. 



■ 



- — .:-:T.il:y, for a piven till 

.'. .... I'lO po 

-, lul 

r. ^ LrrA-;'= lin:p . ., 1^9 
.-—~~-. : ■*,.:■»■ ciiiJic *i2l» 
"■-' -s i:-.:.:::vr:* r.vA'U: oa ih 
-' - i- ic - :.- rn oil, I am enn 
*■ - -'^ '-> -.".•':':. V'.zhi as is t 
--XT...: :..-4':iro. 
- — ■ • . ■ ... 5 iiif) ciihii 

-- - "- "JiiiJU »li 

_. ^.■.-- . *• :-i :::e (ii,*ffrcT.*. m 
• - - ~:. :■: j-'*:.'! :hus: — 
'■-I .L=.l.Ci. it 2*. trf. 

13 

- l-lii?.L-_.i: nu-uiJ 

- - - *- 3 

. -: :-L.:::. At :hI, -2 
... -?!_:, _:-„.« cir^tilcs 

G 

- : :■ 1 



'■~>:.KlL PaINTINTt. 

■■• '_..';• 1 1 . r- ' c'.iiC'Vih' 

.•-: :i .'.::: -'\y.* ,ire. flakf 
■ :r.-f :-:-r. r.-brt, brow 
•• •- :!.L:t rV'---:-in blue. 
..«-• \i'L.i.~. rt-J. King's 

v-.v: rr -l: :-. your dcMcn 

~.- u*r If-::, irrinj oil and 

'.T. * ."T.'iZL.iT in doing t 

■ :.- -■::. ;■:■* *■: dark as you 

-.-*»j. - ■>:.-.:.£ : whiciu al50 

L-. ::..-:. *r s-:-ior?. Thou 

— - > i:. - -- ■■ -.- ! in fainti 

..:■- -:.■■:.: •■; in tiieir 

": ■: ■■jilt and * 

- ■ •! ;.._ :•: ii-.-ac iu thi 

■ : '.'-.iv c'.Hli fo 
. -- •:■: :' rc'-jr-iuml n;: 

■. :.:.::: -. aiiJ then 

... .>.;.— l.et ti 

. V :.-:■.:: --.ry hriirht, g 

'. - •-• -.: the effect i* 

■^T-- -ft '.be fini.«h)nj|: 

:• - r-^t paiutine. t 

':• -*!:■: C the distanct: 

■ ■» ■ •:■: --■ liif croup, an< 

- .- ■• . !^ : st-.-irest parts, 

.—.■ z :# to tind tl 

".;- jr.'-.:nd of shad 

■ .-■ . : .-nd the mi't! 

,-- ■* Tlic sky sho 

1 ;:'.r and loft with 

■ :::•:.'. clouds. Tl 

.-:: taint and obs 

-. ...* I,-. i #.'3:c of their lii 

- '...-t crxmnd-s of thi 
.- -: ' .T-: :r. t^aonch only ti 

i-' ^ i.rJ shadows faintl 

, -. ■ -i r.rTtr to incline m 

.'- : '-■ :!.: \cvy high lights 

*'j:.I; with a liwcetenc 

*■ - s^.:tin and mix the 

,' Vf rt.ichine. 



MAGAZINE OF SCIENCE. 



63 



Patniing. — Be^n with tlic «ky \ and bj 
tlic ft^curc and colors of ihe horiaon : then 
; after that Uy in the general tint of 
finish OD it with the high lights aiul 
tibts that arc wanting wiili light tender 
thai toften the wholt; very lightly. 
finifiking of the aky abould he done all at 
'•Dft p^atinf . Obverre that the stiffer the aiarti 
tttd ooton of the horizon are laid, the hetter the 
doadi mtf be p&intedupon tbem. 

The ){re«lrst diitances ore chiefly made with the 
color of the sky ; as they grow nenrer and darker, 
I^Mvmd eeiunble the parta very thin with such 
i|,rilila|; flisdow color? os eomt* nearest tu the general 
iiwuf die ^roup the objects are tu. Thia glaxin^ 
be understood of a darkish hue. and that 
it paintim^, or dead color, ahould be seen 

it dJstinctJy. 

ire we proceed farther, it wiU be proper to 

Ifooetfaing of the most uaeful glaxing eolom. 

terre Tcrte. Prussian blue, brown pink, 

Sienna, are the prini.ipsl. The more you use 

Ukc Indian ink, and the more distinctly yon 

rthem the better their transparent beauty will 

apjMsar, provided you do it with good 

AAer tbeie glazing colors, burnt 

very good glaxing warm brown, and is 

tific in the broken grounds and nearest 

Make out all the groands of the objects 

glazing shadow colors as s?em nearest lo 

bne of the object in that situation. 

OoloTi that come next for finisbing, are in 

of middle tints. Tbcae should be 

ly laid over the greatest breadths of lighta, 

manner as not to spoil and cover too much 

tglaxing : do it with a good body of color. 

Co these methods, it will be easy to finish 

•c«oad painting down from the sky through 

group. As you come to the firiit group, 

Ihe objects should be perfectly finished, 

Ihcir under or most distant parts before yuu 

[uj of the other which appear ncArer. 

ad I fut Painting. — If oiling i« necessary, 

quantity possible, which should be 

stnrop tool and pencil proportioned to 

It is to be oiled, su as to oil no more 

WUhtcd; then wipe the whole place that is 

nth Q Tiiece of silk hnndkerchief. When 

ly object rctnoinber to use a great 

.cry nearly of the same color — but 

;«f *U mUcu finishing trees. The tnethod of 

near trees is, to make the first lay very 

uinre though not qait« so dark, but more 

dq^rreof a middle tint, and follow it with 

ting the shadows through the middle 

«id. hist of ail, lay the high lights and 

color*. All this cannot be done at one 

i thcrrfore. th« best way is, to do no more 

first Lay with th^iint ohadows and leave 

with improving the middle tinta and 

' ' - them dry ; then add all the lights 

Vir* in the best loflnncr you are 

'.'S in the landscnpe nrr the last 

ire, those in the foreground should 

1 those in the distances should he 

1; fur after the ^gures in the first and 

gmnp are painted, it will be much easier to 

i'»ns of those in the middle part of 

I observe that the shadows of the 

t*.. >..).. »«7 of Ihe flame hue. or color, with 

the |R>ap or pUce they are in. 



7b the Editor of the Magasme of ScitfKe. 

Sir. — I have perused an article in No. 47 of your 
valuable publication, on the convertibility of a te. 
lesoope into a microscope, and cannot but coincide 
with your ideas of the subject. Unt there u anoUier 
method to be pursued, which will not in any mea- 
sure tend tu disfigure, or otherwise injure thegUas. 
The experiments made were upon a large and small 
telescope — the latter the highest in amplifying 
power, as is, I believe, groerolly the ttasc, and of 
the simplest kind, as follows : — 

Unslip the slides, (or take oJF the caps, which 
ever it may be,) which protect the field and eye- 
piece glasses. Place the eye-piece under the eye — 
at the same time have placed anderneath the field- 
glass the object to be magnified, and the view thus 
obtained wtU not only be without detriment td the 
instrument, hut, if the glasses are good, as clear 
as for ordinary purposes could be wished. 

JBOIDIDB. 



7'o Me Editor qf the Magaztiu t^f Science, 
HARNESS PA.STE AND POLISH. 

SiB. — Seeing in No. 53 of the Magazine of .Science, 
query 185 — " What in hameu paiUh and ifg jtri-- 
pnralion .*" I have taken tlie liberty of sending ymi 
the preparation of two, which have cnjojfd (he 
most extensive patronage for some years past. The. 
liriit under the names of " Hantes«-Mak<M'a Jet, 
Ladies* Blacking, fltc.'* Tlie other as " Walev- 
proof Harness Paste." 
Fir$t Receipt. — 

4 as. best glue, 

1 i pint good vin^^, 

2 oz. best gum anibic, 

1 pint good hlack ink, 

2 drms. best islngl&ss. 

Break the glue in pieces, put it in a boson, and 
pour over it about a pint of the Tinegar — let it 
stand until it becomes soft. Put the gum in another 
bason, '(or some other convenient vessel,) with the 
ink, till it is perfectly dissolved ; melt the isinglass 
in as much water as will cover it, which may be 
easily done by placing tlic cup containing it on the 
hob, about an hour before you want to use it. To 
mix thcra, pour the remaining vinegar with the 
softened glue into a aauc«pan upon a gentle fire, 
stirring it till it is perfectly dissolved, that it may 
not bum to the bottom, being careful not to let it 
reach the bulling point — about 180 Far. is tlie best 
heat. Next odd the gum, let it arrive at about the 
same heat again ; add the isioghua. Take from the 
fire, and pour it off for use. Unless the above 
method of niixtng the ingredients is attended to, 
ttie pulish will not have that brilliancy it ought to 
have, if it is not entirely spoiled. To use it, put as 
much as la required in a saucer — ^give it Gufhcient 
heat to make it fluid, and apply a thin coat with a 
piece of dry sponge — if the nrtielc is dried quickly, 
either in the sun. or by the fire, it will have the 
better polish. This answers equally wcU for boots 
or shoes. 

WATER-PROOF HARNESS PASTE. 

Put into a glsited pipkin 2 oz. of bhick rosin, 
place it on s gentle tire — when melted vld 'i oz. of 
bees'-wax. When thia in melted take it from the 



"NCE. 



-r- --^.-f .y thf Toad without Food.— On Sep- 

- : >V,, a living toaJ wa? put iuto Ifac 
: .•-.:• .tplh of eight feet fn»m tht* larfacp, 

■: t.z.\j trravpl, with a tlowpr-]iot reveneJ 

... -. T^r ii. The hole was then filled up 

:: - fi-'^Jf cropped, the spot selected beiny io 

..-;.r=. Tie pit va< opened on August 29. 

'■ *•"■* •^'^Bg been closed three years save tfn 

▼ 1' 1 ■_:- loaJ was found aliTe,' and need ail 

5.*r::i*:.. crawl away. It was not a fnll- 

n n Ti' when taken, neither did it appear to 

=-^-i-***i ia sixe during its incarccratiuD. 
i-» tzT-frrx-eni confirms the statements of toadi 
— ^ • : s: food. In the A/aj. A'ol, fli«, 

- . ; 31:. ij an account of a toad that vii 
i.- .. .- -say nf experiment, in a block of 

- •..:.• 5; jce of thirty-eight years, and at 

- i . : :- 1: 1 oriod was found alive, 

;-vif r.jnfj.— The plants that grow at the 
=. . :' i-c sea are found under all clinuta, 

s^ \i-- %:ii«5itudp* of heat and cold are new 
.; !:■• ':* ::vci. the temperature at ccitain dtptiu 
: • n»h?re the same. Climate iaflupocn 
S..1 1- rri'fcr cronine in ahalldw water. A 

- i^:- *.a-plant (fucus natans) generally 

'.--: uamo ul' sea tang or sea gran ii 

.^-w. .r.ii :Iio ooiiator to the poles. As there 

^ Z.Z. zi- :;uii;lier of marine plants, a gitil 

.: '.j-.z. 170 i.i le found everj where, some, 
■ •■-■.i; :.■ reii-.iirc a more courcutratcd lall- 

. .: - fiUTf wiiilc others flourish most oo a 



CORRESPONDENTS. 

>!• -..a*' ■ ■'■Ti''vt9<-rttc<e in Ihr makintc nt mid* water, i* 
-•• .-. — .rrf. *^« rapiil union i>f the arid xnd alkali; ui 

w* . .*■.. ^L* .. j«raLi?n of carbonic uviJ fri^m the carbca- 

^ -.■». ii-pf 3CX*. Ufc Itip snhilion or rni)|»er as ftroiB 
w « '». - «• lid '.jke cure that the lottlvrlnf; is gOML 

; — >.• i -t-r-A':^.-a if n-iinviie in the recxtpts. 

\ • — ''-\ I vln>p k'f t>il rv-und the iO)i. and lei it muls 

■-. •• i • 1- 1.'^. *Ct>ppvr upwards— ofTen there ii no remrij'. 
S — I ;<; ' ir^thtfA aJrendy givon will not aiw«rer. n btn 

:v .T-. .:«: Tt>c«;'.>t 4nwU|( vur (t>iwrs lonie where. »d«ill 
-v^-.:-] - r .T u «irly aa )i»wib1e. The Nupoleon medib 
.•«• ■ti.i.jf.* •:" 'ype mflii! Kur artificial ivor>' we Vol. 1. 

:-■ — *V- V' l" ..vrtainly resume liw rubjeot neit wwfc 
/ <: .~.V . i<<fz v-f Par:* once ui>ed or ipniied is nnt tc be 
■^-.■- -.^vi.' eisvp: t>y I'uniiii^'. as in its first maoulocnm. 
^\ - .» -Vt'Mi'.vvhniny. «c \\.I. I. We will tboitl; 
■.■\/,j.-T m-.-jv fuly the pror«>». 
«. ( vs.— Wc wvu endeavour to ublife him. 

' .■i. V^fx-xix. — llie mistake arose from two c«R*- 
, ..<-■!■■* ;:«:p^ Ihe *.ijiie signature. 
. . i-v Vvu «•' -.fvervvhehned wilh letteri thii week, tiH' 
* . -tfu :; V . ^.tilh^Dt.? iif out fneodi lill ournexl Ntunbcr. 
■. Kj Ttfv *tA.\ iiil be answered. 



N . 



T't^ Vnb'ie are rrtpeet/vtly n^famud, /W 
■. h •/ this Magazine it now ready, btmmd * 
> J id ietterfd, price 8«. // eontaint uytrer^ 
_V0 .'^:-,:Httt articiep and i* emhelliMked iri/l 

r ^fi. '-fftfredj, /br Hnding, nuxy aUa *« 
'■ :;•■ {\e FHblhher, price lOrf. 



[:.<uft, II«okt for Heview, Inventions for lllw 
.- . ii< be adiireued to the Editor, at ii. Gnat 
:.v: I > <lu' Printer; or tu the Publisher. AQ 
!*: Is* ivji paid. 



.-.-. \ ;> Krakou.G. Wbilellonie Ldne. Mile KndRoad. 
r-. .■ ■> '.\1 1-\ ory S.iturdaT by W. BatTTAlic, 1 1 , Patcnurtlt 
v.w. .ui.i mjy be hadoi allJfuokielleri and Vewmwa is 
li'Wti and Country. 



^lAGAZINE OF SCIENCE, 



ana Sffeool of arts. 







■Hurra that there are onmerous of our 
whom aa scoount of Ibe lutuL gnlvanir 
• parlicoUrly such as are adai^ted Co oc- 
or Kt in action the galvanic fluid, will be 
The prtacal paper will be devoted to 
n of simple circles, or such galranic 
composed of a single pair of elements. 
ffKurral principle that j^^i^viuiic action is 
panicd by chanical actioD. Tu disturb 
U. 



the galvanic fluid, Iherefore, it is only nccesMry to 
unite together two mrtals, nxid inimerce tliem in a 
fluid which acts chemically u[K]n one of them, in a 
different manner fruiu the utber, and galvanic dis- 
turbance takes pUcv. That iinch i« not alwnys ap- 
parent arises from the non-employment of an instru- 
raentt delicate enough to detect the quantity of 
fluid put in agitation. 



tormalf 

i* a wen u a 

viUbfsfterwi 

of tke nrnple gairi 

Ik vtare the ti*o met»l« 

in thr Iii]i 

c>cb other. 1 

riiutaiicf, |tts! 

tfaen throQgb U 

afUD it rcM 





rUl be the fl 

to Ak ok of the plate* 

email 

isMe effect, yec; 

the iBper^cir* act« 

flf the fluid set 

Mr. Hare, of 

jilranjc circle, 

which allhoBgh 

f be thoofht • 

a realitj »o united tp| 

e par of each kind. ~ 

■ haaCiiic flnida thi 

Ml it had to pikaa, audi 

It imiMiiil in 

tt to 

«r m haat morer. A bat 

itoder the dii 

tostirutioD. It ii 

Fig. 5, and M>nsisti 

^f, coifed runiid each othi 

d 1 fcrt wide, the whole 

ll was «b«tfcd by I 

dOaKeKid, 

raM^Kftal ap. wheo lla 

m hr lualiMiiil, Tiro wlre« 

waA dkecttf aMtal, aad iU effect' 

lo approach each 

U and powerful. 

eada may be formed with 1h» 

^_ tf ifae pklea beiag soldered togetbM 

' Cs & mktm Ihr amt and copper are em 
fai^ ^Ib yd file action will be eoQ 
a Jbmkm is between the melalj ; i 
VT BaBT traaotu, an extretnelj at 
I 0«aaamapaMCparticularIjif thedimus 
^tttfto- f hBlMBaibl^'lvkAe the direct actioo i» pn 
,^ ftgteiCtov litfMi^lftrtoa^alBlealitliBiaipediTnent up 
_ 4f r k^«itolfc»paMii(i»ctf the fluid diftturbed. 

h «teA w( t A linaliiaMeor galnnic cirrle maf be 
tenf ifew<» ' tf a ^V> ■■*!, aad two difTerf nt fluidi, 
bL fMit? a AfcaM ftliaaie action upon the mctaL 
: ^ MMk fl^fVM • iMi tf BBC be cemented in a boi 
«it 1^ 9^ 7. SM aA «»d water be pourrd in Uin i 
. ifa»* I mm Bifa af It. aad aeid^ted water in the, 
dl Aa mitm wdl tabe place, and cont 
ia •■» mA ad a cvrtnt will paaa roond. 
I lfeiB( M9 W cAcced Biany wajrs — it 
if fpaAadaiK «■ — ruaal Aimiical action, 
)f ^ wd wdH atew «a BocAed. if it be 

«f Aa lint, and oold on the other ; 

ba t a ag fc oa cue aide, and «m< 

^ |Maft aiiat. A h— hdfcii of this fart 

- «■■* ' Ifc. Sfm^gmm tte pniprietjr of amal 

h «vkito . bk aawrtaf «Mi Beroiry one rarface of 

p« «iM nii W dU bf werdy immersing it for 

mmmMw ia the alSnte of mercury, or el«e « 

4M 1 • m ajlria Mad, and then rabbin'g raervury i 

TTb Ae ramitmmd.J 





MAGAZINE OF SCIENCE. 



VARNISHING. 
wmmedfmm pogt 56, and condudtd ) 

ni Vami$H or Goid Siec/or Giiding. 

1 oz. gnm sandanic, 
\ ox. ^im gtillae. 
I oz. (arpentinr, and 
o oz. es»cace of turpentine. 
artists who mnkc tu« of mordrint, sub- 
the tarpealine an ouucg uf ibc cssonro 
dm, vhicli renders ihU cumposiuon iliU 

Be- 

nil.thr compoiitioD of mnrdantf! admits of 

Ddificalion, nccording to thr kind of work 

llp'y Mc destined. The ftppUcaiion of 

►weTcr, is confined chirflv to gx^ld. When 

Hired lo llll up a design viiKh pold leaf on 

nd trliatcTcr, i)ie ruoii>osition which is U> 

the means of union between th(« metal 

le ground, oxi^ht to be neither too thick nor 

tid ; becADse both Uiese circumstanccfl arc 

V injurious to delicacy in the strokes; it will 

^uiattc also that the composition should not 

the artist liu completed his design. 

Mordant*. No. i. — Some prepare their 

; with Jew's pitch and drying oil diluted 
of turpentine. They employ i( for 
e gold, or for bronzing. 
axtista imitate the Chinese, and mix with 
rdanta colon proper for aAsisUng the tone 
I0y ue desirous of giving to the gold, such 
r. red, Ac. 

employ merely fat varnish . to which they 
Ue red oxide of lead (minium). 

make use of thick glue, in which tlicy 

a little honey. This is what they call 

When they are desirous of heightening 
' of the gold, they t'liipLuy thut glue, to 
e gold leaf adheres rxciMtdinply well. 
^The qualities of the following are fit for 
lad of application, and particularly to 

Expose boiled oil to a strong beat in a 
kon a black, smoke is disengaged from it, 
t fire, and extinguish it a few moineni« 
putting on the cover of the pan. Then 

matter still warm, into a heated bottle, 
lo it A little essence of lurpculiue. This 

diies vcty spcediJy ; it has body nnd ad- 
, Aod strongly retams, gold luaf, when 

» woud, mulalK, and other substances. 

i /or Palm and coarse Wood-work. — Take 

tiW of tar, and grind it with as much 
brown as it will bear, without rendering 
icfc to be used as a point or varnish^ and 
Aad it on the pales, or other wood, as soon 
Dient, for it quickly hardens by keeping, 
nixture must be laid on the wood (o be 
by a large brush, or house painter's 
;d the work should then bo kept as free 
ftnd insects u possible, till the varnish 
ughly dry. It will, if laid on smooth 
iTe ■> verr good gloss, and is an excellent 
tinn of it Against moisture ; on which 
as wf«ll as its hning cheaper, it is txr prc- 
Q painting, nut only for pales, but for 
iKMrdtng, and all other kinds uf wood- 
r grosaer purposes. Where the glossy 

lor is not liked, the work may be made 
rish browD, by mixing a small proportion 

lead, or whitiug and ivory bhick, with 
brown. 



A Black VamisKfor Old Stratt or Chip Hatt, 
\ oz. hi^ax blai'k sealing wax, and 
2oz. rectified spirit of wine. 

Powder the sealing-wax, and put it with ilie 
spirit of wine, into a four-uunce phiol; di^ffstthom 
in a sand heat, or near a fire, till the wax is dis* 
solved ; lay it on warm with a fine suit hair-brush 
before a fire or in the sun. It gives a good atilf- 
Dess to old straw hats, and a beautiful glos^s, oqnal 
to new, and re.iistfl wet. 

To make Varninh fur colored Drawings- 
I oz, Canada balsam, and 
V oz, spirit uf turpcutine. — Mix them together. 

Before this cnmposition is applied, the drawing 
or print should be sized with a solution of isinglau 
in water; and when dry, apply the vamiah with 
a comcl's-hair brush, 

AtuAktr Method. — Dissolve one ounce of tli« 
best isinglosa in about a pint of water by boiling 
it over the fire ; strain it throagh fln« muslin, 
and keep it for nae. 

Try the size on a piece of paper moderately 
warm, and if cUstcns. it is too thick ; add more 
water : if it soaks into the paper, it is tuu tJiin ; 
add or diminish the isinglass till it merely dulls 
the surface ; then give your drawing two or throe 
coats, letting it dry between each, being careAiI 
(particularly in the first coat) to bear very lightly 
ou the brush (which should bo a flat (in camol'i 
hair;) and the size should flow freely from il, 
otherwise yon may damage the drawing. 

Then lakts the best mastic varnish, and with it 
give at least three coati, and the effect will 
answer your most sanguine wishes. 

I'his is the method used by many eminent 
artists, and is found superior to any that has been 
tried. 

Another f'omisA /or Prin^-— Dilute one quarter 
of a pound of Venice lurpeutine, with a ^ijjL or 
thereabouts, of spirits uf wine ; if too tJuSc* a 
little more uf thts hist ; if not enough, a little 
more of the former, so that you bring it to the 
consistcni'e uf milk; lay one coal of this on the 
right aide of the print, and when dry, it will shino 
like glass. If it be not to your liking, you may 
lay on another coal. 

To make Famish far Wood, which resiiU the 
action uf BoUintf IKale/-.— Take a pound and 
a half of liuseed-oil, and boil it in a cupper 
vessel, not tinned, holding suspended over it, in a 
small linen bag, b oz. of litharge, and 3 uz. uf 
pulverized minium ; taking care that the bag does 
not touch the bottom of tlie vessel. Continue Uie 
ebullition until the oil acquires a detfp brown 
color; throw into the vessel a pound of yelbw 
amber, after having melted it in the following 
manner: — Add to the pound of amber, well pul- 
verized, two ounces of linseed oil, and place the 
whole on a stionfi tiro. When the fusion is com- 
plete, pour it boiling into the prepared linseed -oil. 
and continue to Icavu it boiling fur two or thrco 
minutes, stirring the whole up well. It is then 
lct\ to settle £ the compueitiou is decantered and 
preserved, wnen it becomes cold, in woU-corked 
bottles. 

After polishing the wood on which this varnish 
is to be applied, give to the wood the color re- 
quired ; for instance, for walnut wood, a slight 
coat of a mixture of soot with tlie essence of tur- 
pentine. When tJiis color is perfectly dry, give it 
a coat of vamifih witli a t:ne sponge, in order to 
spread it very equally ; repeat tiieso coau four times, 
taking care always to let the prcccdiiig toat ba 
dried. 



MAGAZINE OF SCIENCE. 



Oil Vamhh.—VkoW one pint of tlio h^ex linftocd 
oi], nn huiir, th4;n add n (|iiiiitcr of a [H>und of lh« 
cleared roflin in powder; atir it well lUldiaaolTed; 
add ono ounce of spirits of turpcutine ; strun il, 
and bottle for nsr- 

ThU U R cheap and good varnish for sash 
frames, or any work whoTC economy is requirvJ ; 
it has, besides, the property uf buariiiK hot water 
without being damaged, and is not subject Lu 
scratch. 

To yamUh Barjm and Dulcimera.^ViextKxe the 
work with eixe aud red ochro, thou take ochre, 
burut umber, and red lead, well irroundf and mix 
up & dark brown color in turpentine varnish, adding 
aa mnch oil of lurpentiue that the brush may just 
be able to pass over the work fair and even. 
While yet wet, take a mu&lin sievp, and sift as 
much DuUJi metal, prerioiuly powdered, upon it. 
U is requisite to produce the etfect, alter whicUt 
vamiah and polish it. 

To Vamiah Otasa. — Polverizea qtumlityof gum 
■dracaulh, and let it dissolve for tweuty-four 
hours in tlie wbito of epgs well beat up ; Uicn rub 
it gently on (iw glass with a brush. 

To yamiah HaUoona, No. I. — The composi- 
tions for varuishing balloons have been variousLy 
modified ; but, upon the whole, the most approved 
appear* to be the bird-lime rnmish of M. Faujas 
SL Fond, prepared at\er M. Cavallo's method as 
follows : " In order to render Unseed oil drying, 
bnil it with'i ounces of sugar of lead, and Sotinces 
of litharge, for every pint of oil, till they are dis- 
sotved, which may be in half an hour. Then put 
a pound of bird-lime, and half a pint of the 
drying oil, into an iron or copper vessel, whoso 
capacity ^ould equal about a gallon, and let il 
boil very gently over a slow cliarconl fire, till thu 
bird-lime r<Mi5)rA to crackle, which will be in about 
hali^jp three -quartt^Ts, of an hour; then pour upon 
it twoand a half pints more of the drying oil, and 
let it boil about an hour longer ; stirring it fre- 
quentlv with an iron or woodeu spatula. As the 
vamisu, whilst boiling, aud especially when nearly 
ready, swells very much, care should be taken lu 
remove, in those oases, the pot from tlie fire, and 
to replace il when lUu vaniiiih subisidcs ; otherwise 
it will boil over. Wliilst the stuU' is boiling, the 
operator should occasionally examine whether il 
has boiled enough, which may be known by 
obser^'ing whether, when nibbed between two 
knives, which are then to be separated from one 
anotlicr, Uiu varnish ft'niis threads between them. 
as it must then be removed from the fire. When 
nearly cool, add about an equal quantity of oil of 
turi>eutine. In using the varnish, the stuff must 
be stretched, and the varnish applied lukewarm. 
Id 2-i hours it will dry." 

N1>. 2. — As the elofttio resin, known by the 
name of Indian rubber, has been much extolled 
for a varni.'^h, the following method of making it, 
as practised by M. Blanchard, may not prove un- 
acceptable. — Uissolve clastic gum, cut small, in 
five times its weight of rectified essential oil uf 
inrpentine, by keeping them some days together : 
then boil 1 ounce of this solution in 8 oiuices of 
drying liniieed oil for a few minutes ; strain the 
Bolutiun. and use it warm. 

To Varnish RarfJUd Air J5a//oofiff.— With re- 
gard to the rarefied-uir machines, M. Carallo 
fucoramends, first, to soak the cloth in a solution 
of wil-ammoniac and common bize. using one 
pound uf each to every gallon of water ; and when 
thft rUilh is quite dry. to paint it over on the inside 
with some earthy colur. aud strong size or glut*. 




led wft$ \ 



the^ 



Ei 



When this paint has dried perfrctty. ii will ttm 
be proper to cover it with oily vamiah. which mi^ 

dry before il could penetrate quit'- <>r-^ v- >»'. 

cloth. Simple drying linfieed oil ^^ 
purpose as well as any, provided il 
tluid. 

To Polish VamitA, — This i» cflcctod vftht 
pumice-stone and Tripoli earth. The 
sitine mu.^t be rcdurcd to an impalpable 
and put upon a piece of serge moiMcneil 
water ; wiih this rub liglilly and equally the 
nishud substance. The tripoli must aUo be ; 
to a very fine powder, aud put upon a cleau wi 
cloth, moistened with olive uil. with whf 
polishing is to be performed. The vamiah 
to be wiped off with bo1\ linen, and when 
dry, cleaned with starch or Spauisb while, 
rubbed with the palm of the hand. 

Colors proptr for Coiored VamisieMu — 1 
— Lamp-black, carefuUv washed aud 
dried ; or block obtained from burnt vino 
or peach* stones. 

Ke/toirs.— Yellow ochre, yellow pink, Ni 
and Montpelier yellows. In mixing up 
two, a horn or ivory spatula, with a glass 
and mortar must be used, because these 
are hurt if touched with steel or iron, 

BlwK. — Indigo. Prussian bine, bhie 
and ultra-marine. All these must be reiy 
powdered. 

Greena. — Verdigris, distilled or crysli 
verdigris, and green compounded of yellow 
blue. The verdigrises will require a mix? 
white, varying from one fourth to two 
cording to tlie tint inlcnded tu be given. 
white lead. Spanish white, or ceruse may be i 
for Uiis purpose. 

Reda. — Vejmillion, red lead, red ochre. 

Purples. — Cochineal, carmine, SLad 
lakes with cenise and boiled oil. 

Briek Red. — Dragon's blood. 

Ruff'. — Dragon's blood, with a Little v< 

Viokl. — Hed K-od, mixed with lamp 
a slight mixture of blue and white. 

Pearl Grey. — Comae mixed Mfith hunp-hl 
or ceruse mixed witli indigo. 

Flaxen Grey. — Ceruse mixed with carmii 
lake, aud a very small quantity of Prussian ' 

MAKING THE NAPOLEON M£DJ 
(Rn Cltcko.J 
OcB readers most have frequently seen Uie 
impressions, or nwdallions, struck from Che 
Intionary, Napoleon, and other medals du^g'l 
wars with Prance, and vhich were u^nally 
mounted iuto tlic lids of snufl'-boxes. and defe 
from injury by being covered with convex gl 

It is a fact, that either from a medal si 
any of the usual metals ; from a aqft sted 
even from of these medoUions tbesaselvcs, dies : 
be readily made, each of which will be 
striking a considerable number of such mi 
and each of these in its turn be cnp.tble of 
ducing a multitude of other dice, likewise 
become the origin of as many suocesalvc in 
aud dies; so that by this means, the urigiaal 
may be copied almost ad injlnitum / Each 
from t!ie anginal, however, losing of course 
thing of its sharpness and accuracy of 
although much less than might be supposed, 
greatly less than by the usual methoda uf ^y] 
medals, by moulding and casting thetu. 



block. 



MAGAZINE OF SCIENCE. 



69 



Rtot but be iur|>rued that to valuable nn 

hitherto, in this iwuntry, havr remained 

bands I as, from the succeed Jnir detail*, 

Sound to be ^ondaatly simple and easy 

^pfat tmed in forming Ihe Dien and tht 

~1\\\4 metal ia composed of Che ordi* 

/«/. which ia an aJlof of lead and re^a- 

ImODy, to which ia added more and mora 

on triiU, hj rc^pcntcdly hrraking a plate 

the miztnre, it is found to bead a little 

lUag. Tbia IB cue of the be-it critcrioos 

^■||M« from the varietT of proportions uf 

Pl^iilua employed by differeat type-fuun- 

r«rtaia j)roporttonB can be ascertained in 

oaition of the broken typa, which are 

ftir this use. 

mpound metal is made and melted in a 
Kit. such as is used in oookinf^, and which 
leJ over the lire by its baU or handle. 
when a small quantity of it ia taken ap 
ladle, and kept in continual motion by 
e ladle roand and round whilst it is cool- 
ra^h aasumei a ptuty connitence, or a 
DCDt of cry stallizBtion : this is the pro[ier 
r employing it either to form a die or a 
by itriking the original medal or medal- 
die upon it, in the manner to be hereafter 
hen, from its pasty coherence, it can- 
iway from the blow, and is yet sufficiently 
receive the impression of the medal or die. 
pound metal at the abofe period doea not 
,t CDOugb to ainge, or even to diicolor the 
which it is laid to receive the impres- 
tbis aguo forma auother valuable crite* 
idge by, whether the alloy is rightly pro- 
or not. 

Id hardly be thonght that this alloy or 
M aboald be capable both of forming the 
lobl, and of yielding also nnmerous Im- 
Grom it, and yet sncb is the fact : a most 
c discovery, and one, indeed, upon which 
m^rit of the art chiefly resta. 

ai may consist of nlxiut five parta of 

of regttlaa of antimony. The lead being 

iron reaael. the regolus must be itirred 

butaOyf and be kept immersed in the lead, 

at length diasolved or melted in it: this, 

U a work of time, and very mach dependa 

ifvf hect given to the lead, which ought to 

its melting point, Chough not much, lest 

Oiidate it. The surface uf the lead ought 

t covered with rosin, pitch, or grease, to 

oiJdatioa as much as possible. Very 

pwdocsa of the type metal depends 

juality of the rcgulus which enters its 

ton. As, for instance, it contain!^ more or 

or tin (the clippings of tinned iron plates 

rally preferred in lliis country for making 

Itts from the ores of antimony,) or cvpiter, 

partiruJarly recommandrd for making a 

tittcM-, than the regulus made with iron, or 

trty free from any admixture with either of 

Raia, and which is the case with a very fiu> 

of rcgulus we have seen recently ; so 

Matt uf the type metal, as we have before 

ly various. 

Tia are also taken by the French 

" Dnrrrt'M atlny,^* but which wc 

name of Sir Unnc Xewton's fu. 

g a compound of three parts of tin, 

aud eight of biamnth, and capable of 



melting ia boiling waler. Thu metal, although 
more expensive, is harder than that above described, 
and is capable of giving exceedingly sharp impres- 
sions. A still better tuetal would, however, be, G, 
.Sn$Uh*x KolHtrfor tin, as it is not so liable to crya- 
Callize in cooling as the fusible metal. This is 
composed of one part of each of lead and tin, and 
two parts of bismuth. 

AfipuratHM rmploiiedL—TUe machines used in 
striking these medaljinnn ore various; the common 
screw itTvss, will answer this purpoM loJefAbly 
well, though the gradual pressure wijjch it gives ia 
not 10 be ci»mpartd to tlie effect of a sndtlen blow. 
Another nu-thod, and one which we have tried 
with perfect success, is lo pour the mulal on a 
thick felting of leather or paper ; when it begins 
to ronl so as lo be scarcely fluid place the copy 
upon it, rcitt a flat-ended stick upon it, and give 
the top end of the stick a sudden blow. Hie 
followinir figure shows a neater contrivance for 
the saine purpose, it repre<u!nts a stand witli an 
upright bent arm, Chrongh a square hole, iu the 
top of which passes a square si>lid rod tl. Tho 
metal is poured into the metal cup A. and, when 
at the right di'greL- of heat, the rod II which has 
the medal fastened with a bit of wax to tbe lower 
end, is to be let down, aud u sudden blow lo be 
given to the top, when tho lorce will cause the 
impression to be a gootl one, if cirefully ptTfornied. 
After the medal) iims are !*lruck, tlic back« (»f Uiem 
are tnmed flit and the eiigca turned evenly round 
in a lathe adapted tu tlie pur[>oae. 




4^ 




On Bronzing (^ MedaUitmt. — To perfectly 
sui-ceed in broninng these metlallions, we must 
euipUiy the two foUoiving Miluiiims : the first, 
which serves as a preparatory wash, tn be use<l oa 
hereafter <lcxcribcd, is compoaed of »iir jiart of 
sulphate of iron, one part of sulphate uf cop]>er, 
ami twenty parts (by weight) of distilled water. 

The second s'llulion, wiiicb \% the bronze, is lew 
complicated j it is composed of four parts of ver- 
digris, and sLXtL-en ]iarU (by weight) of white 
French vinegar. 

The manntr of employing thest SoliUitmt, — 
When the medullitin^ Imre been filed and polished 
on tlicir edges, and strongly rubbed with a brush, 
wetted with a mixture uf tripuli, or Tuttcn-stone 
and water, and well washed and dried, we puss 
the first solution slightly over both tlivir faces, with 
a hair pencil, and tlicn wash and wipe the nicdiU- 
Uon dry i tliis givi-s them u »li^'htly btnektsh eoloTf 
and ca.u-*>L-s tlie verdigris tu adhere mure uuickly tu 
Ihcm. They are Uicu nibbed with auwUicr hair- 



70 



MAGAZINE OF SCIENCE. 




fn'iiril. netted with tlio MconJ solution, ontil lli« 
Dccnnu.' rti a dorp copper colr»r ; Iliey arc then len 
toflry for an lionr, after uhich they are {KijishcH 
with B soft brush and red lead, bn^aihint^ upim 
them fr«iucnlly, \o siiehllv nmistlcn iliein. and 

u** Ihf red lead to mdlicre to them ; the fMli«h is 

itlv finislied with a Mifl bru!ih alone, paxfiing the 

Tu^h fmtn time tn time over the palm of the 

hiiiid. To prevent the bronxes froiD l>vini;attacke<l 

hy liumidtty. Ihey may be eoveri;d with a (light 

foat of gold colored Ineqaer. 

The tlirlira made with Darc-et'i nlloy, foiible 
metal, arc bronErrt with the second mhitinn only, 
and t\o not require to be varnifihed to prrscrre 
tlirro from (heetTecisuf humidity. 

The plumbers give their ftoft soldered juinta 
near ibc f^oiLstht-appeamnceof cnp|)er. by ^ping 
liver theui a mixture uf sulphate uf copper la 
]KiHder, nith rtni'^r 

Tlir iib<i*e niediUlions are frrquentlv hnnized by 
coating tbcni with a tliin luvrrof ti'tld, itxc, and 
(ben applying btonxe jMivilcr witli a dry hair 
pencil, in the usual m^nuer uf bronzing plaster 
fignrvs, Akc. 






WOODEN MARBLES. 



■ifrB genUemsn, M. C. Malo. hi« discovered 
the sfxnrt o(f tmitaLmg, by means of a peculiar 
wooden paxte (without any Inlaid work or incnuta- 
tioii,> the uoit prcdovi and rare sorts of nataral 
marbles, aud creating, according to tlie dictatea of 
fancy or imagination, such differenl aorta of 
marble »% nature dnes not produce. 

L*p to this period, mnrble could only be obtained 
fnim natnrr, but tii futurr, by the u£e of this In- 
vention, the hchf-dt and rarest niarblea can be 
produced, with those ibuu^and accidental fiaaarcit 
Trina, shades, and Iranyparencio, Stc.f which the 
ablest painlnr ran but imitate on tke Kurfaet^ with 
great expense, and after all, insufficient in its 
cxecutiott as well as In result. The patent marbles 
can be made of ahj sixe or thiclmtu^ and with a 



eluming perfei 
Hu euatan 



rfectioD. 



k 



grMitestaoUdity, and does not want ooy re-touching 
or amelloratjuu for many years. It can be washed 
and clmord with an ordjnary sponge. In caae of 
aocidcot, ur many years wear, it can be scaled and 
re ne we d In the same way as common wood. The 
abarlnga thus taken off will show erery vein of 
marble tbua imiLated, leaving the underpart with 
all the veins, shades, and poliah enkire. and without, 
III any w«y. lojwlag the flolah or beauty of the 
workmaniibip. 

This disocnerr opsM u istsieaae field in England 
la all tke manroeMnn of cnUaeC work, omameo- 
tal '"■■ and, In fact, not only wherever 

«d;<. usf-d this imitation enn be adopted ; 

oac of in the manafactuie of 
, aa well as In objects of the 



II can ur 



whrravrr (b« most magnifinpnt marble may be 
reqnirvd it may be producetl with veins of gold, 
atlvtr, moiher-of'pearl, and, indeed, it can br en- 
licbod «ith all the woodcrt of tho mineral world. 



Um 




8P0NTANEOCS COMBCSTIOX. 

Many vegetable enbstaneeH, highly 

honped together, will hvat. ■'^^^. maA 

burM into flame. Of these. O^" " 

IB a mixture of the enraiwti 

ousseeda, aa rape, or I&nMsd 

dry vegetable fibre, such as hesnp, c^ue*. M 

Ac., and still more so, if also imU«d Ww 

black, or any oihrr rarbonnc«inw 

These mixture's if kept for a time 

close bundlen, and In a warm 

in small quaulittea, wtU uflen brat, and 1iun< 

n smotlicred ftre fur some hour* «n4 J 

admitted freely, will then burnt irtto 

tlii.^ without doiibi, may be atlrnHaiad 

accidental ronflag^rations in ttf 

iilaecs where qnantitica of theve mI 
Lcpl. ludeed this has ber^ .•»..»-. 
cxprrimcnta. The moat im[ 
mado by Mr. Georgp, flnfl 
Hoyal Academy at Pct<' 
in conavqucnce of the ' 
frigate in the harbour m i r>>iv*;'f'.i 
flagration of a Urge hemp magaxmr. t 
place in ihe same year ; and a slight ht%, 
another frigalc, in the same pun, in ihc^ 
year. 

l*hese accidenta led to a vr:^ 
of the subject, by the Rumib 
it came out, ihalal the ti . .iho »r< 

several parcels of roatti: U nack- 

In which Uic soot of t^.... .., v.,.oa huL 

mixed with oil, for painting the tM*. I 

Wing some timn on the floor of the ?«Ma. 

the fire broke out. In cottsei|ttet: 

portant discororr, forty pounds of 

wore well soaked in about Ihirty-titr j-f^m 

hemp oil vamiah, and the whole was 

in a mat, and put in a close cabin, la 

sixteen houn it was observed to glee oaia 

which rapidly increoacd. and whon thr Am 

opened, and the air freely r 

burst into a flame. Throe \ 

were mixed with five pounds oi urtun ou , 

and tlie whole bound up in linen, ana llwft 

a cheat In sixteen houni, il omltlW 4 

nauseous putrid smell and st4*«ai ; o^i'l tw« 

o/lerwarda, it was actually on 6rt« a^d ^'^''^i 

ashes. 

In another experimenlf tSie 
took place, but not till forty-ese 
mixture had been made ; and in 
similar experiments, they all suc««ed«d 
kindled sooner, in dry, than ia ralay 
Chimney soot used instead of laap-hkch 
answer, nor was any ofl^ect prodaceit, 
turpentine was subatilated for the 
oiL In general, it was found, thai the 
tion took pUce more rei^iiy with tJbe 
more unctnous fii -black, than with the isi 
but the proportions of the black t* U* oil 
appear to be of any groat miimroC 
in wet weather, these rotxturca coly 
for some hours, and then coulvd 
actu&llv taking fire. 

In ail these cases, tho soot or hlark, 
wood, and not coal. The pnsseftoe of 
oe any other dry cArbonaceoui 
necessary however ; Ibr, spontaneoos 
will takr place in hemp or cotton, simply 
in any of thme cxprcesrd oils, whan Ift 
fable quantity, or uador oiicBaiauacca 
lothisprooew; MJahot wwlhw, ur »| 



MAGAZINE OF SCIENCE. 



71 



up. An acciilent oT this sort luuipcncd at 
Sunaboron^i. in Lincotnahire, in July 179-1, 
tth a bale of j\m of 1201b., accidentally soikked 
np^oil: which, ftftcr remaining in a warehouse 
reral days, began to itnokc* to emit n most 
smell, and finally to burst out Into a 
ITioleot Uame. A similar accident with a 
^quantity of the same matciiaU happened st 
ij, A bottle of linseed oii hoA been IcA 
ig on a chest ; this bad been tliruwn down 
ident in the night, the oil ran into a cheat 
ooptaiued some coarse cotton cloth, and in 
inuoK the cloth was foand scorching hot, 
laced nearly to tinder, the wuud of the 
i&lso was charred on the inside. On sub* 
It trial, a piece of the same cloth was 
in oil, it was scorching hot; and on 
the cloth it burst into flame, 
to this, is the spontaneous combustion 
voollen yam, which hm occasionally 
when large quantities have been kept 
np in rooms little tired, and in hot weather, 
with which wool is dressed, which is 
tly rape oil, appears the chief agent in tliia 
lUon. Even high dried oily or farinaceous 
r, of any kind, will alone take fire, when 
in circnmstances favourable to this process. 
^fioar roasted till half parched, and of the 
of coffee, and wrapped up in a linen cloth, 
!n found to heat -holcntly, and to destroy 
ilolh. Wheal flour, when heated in large 
and highly dried, has been known to 
in hot weather, causing accidents in 
Fsod bakers' shops, An accident of this 
~ tied by Count Morrozxo, in the Memoirs 
Turin AcadcmVi to have happened at a 
[trarehonsc at Tunn, containing about three 
of flour. It began by a Tiolent 
on a Ismp being brought into the 
and the whole was soon after in flames. 
alone also has been known to take fire 
ler mills, when quantities of it in powder 
ibeen kept for some time closely packed. 
"ler. and totally different species of spon- 
combustion, is that which occurs during 
lygcnation or Titriolizatiou of pyrites, or 
)U of iron, copper, &c. 
cnriouB. ana, if not well authenticated, 
Ifoely credible species of spontaneous in- 
ition. is that in a few rare inalanccs, known 
irio the human body. It is not quite certain 
sther the first inflammation lias been 
ineous, or caused by the approach of 
aubslance -, but in these melancholy 
ints, the body of the unfortunate sufferer hn^ 
(hrougbltoaslate of such highcombualibiUty, 
flame once kindled, has gone on without 
Ibcl, to the entire destruction of erery part, 
bones and extremities excepted,) and as it 
I, has been attended with actual flamet of 
ibrat Caint light. This change is the more 
ible, as the human body, in all its usual 
both of health and disease is scarcely at all 
" combu%tible, and cannot be reduced to 
rithont thf njtsistance of a very large pile 
its, or other fuel ; m universal eicpericnre. 
▼cry aiicirrit mode of sepulture, and the 
-' ins, abundantly shows. Coses 
-lion on record, have occurred 
_-. Two of them, well au- 
l^iticatnO, are recorded in the Philosophical 
LianA, and occurred in England ; and a 
in Italy. France, and elsewhere. In 
one, tiie subjects of them Imvc been 



females rather advanced in lite, of indolent habita, 
and apparently much addicted to spirituous 
liquors. 

The accident has generally been detected by a 
penetrating fetid smell of burning, and sooty films, 
which have spread to a great distance; and ihr. 
suffcren* have u; every insumcc been discovered 
dead, and with the body more or le«a completely 
burnt up, leaving In tlic burnt parts only an oily, 
crumbly, sooty, and extremely fetid mutter. 
Anotlicr circumstance. In which all these cases 
agree, is the comparative weakness of the heat 
produced by this combustion, notwilhstandmg th< ' 
very complete disurgtintzatiuu of the body itself, 
so that the furniture of the room, wooden chairs, 
&.C., found within the reach of the burning body, 
were in many instances absolutely unhurt, and 
in others only scorched ; the heat not hsviug 
bccu strung enough to sot them on (ire. It is 
impossible to give an adequate reason for this 
remarkable change; nor dues it seem before the 
Tory time of the accident to have produced any 
very sensible alteration in the appearance and 
functions of the body, which is certainly a most 
astonishing circumstance. With regard to the 
effect which the tisc of ardent spirits is supposed 
to have in this case, it is impossible not to imagine 
that this cause may contribute largely to such a 
change ; but the instances of the abuse of spiriUi 
are so innumerable, and those of this surprising 
combustion are so extromoly rare, thnt very Utile 
satisfaclion can be obtained from this explanation. 
Hydrogen gas enters largely into all nninml, 
vegetable, and many mineral compositions. 1 1 encc 
it is freqnenttv set at liberty by termeniation or 
spontaneous aecompositiou in bogs and manhes; 
when free from electricity or some other accidental 
cause, it is often set on fire. This phenomenon 
has been observed in almost all ports of the world. 
In Persia it is converted into a pictu fraud by the 
priesthood, who by means of hollowed reeds, 
convey the cnrburelted hydrogen gas Into one of 
their *tcniples, which has been purposely built 
upon ground abounding in bitumen, naphtha, and 
other inflammable substances. As the Persians 
have alvrays been worshippers of fire, the im- 
position is a happy one, for in this temple, they 
are continually feastfld with a view of their Deity. 
At Moulton. near Northampton, in the forenoon 
of September 11th, 1810, a fire broke oat in an 
aah-spinney. Mr. Marsh, the proprietor im- 
mediately went to the spot with some frieuds, and 
found the fire iuuing from ihe earth in many 
places, and in a short time it would hnvo com- 
miinicatcd to a gorso cover, had it not been for 
the timely asnistaiicca of several persona whom 
curiosity had brought to witness this extraordinay 
phenomenon. As there was some lightning during 
Ihe morning, it was imagined a fire-ball had been 
the cause, but it was generally supposed to bo 
occasioned by the excessive (lrynr.«i5of the ground, 
which had been a bog, recently drained for 
planting \ and that the extreme heat of the sun 
liad caused it to ignite. 



STAINING WOOD, Sw. 

.St\imn« wood is altogether a diflTerent process 
from dying it, and requires no prvparation before 
the stain be applied : it is peculiarly useful to 
bedstead and chair makers. In preparing the 
stain, but little trouble is required; and, gfuerally 
speaking, its opplication differs very tittle from that 



4 





tfcjf tiUr.&mlpTi' <) 

ftr awv flf thi* nM f| 

yrt extant are uf H 

■ j*iiwfcr« 8r*| writlen. 'I i| 

ui it> darabilitf nt :J 

Af ftituation ainl keep 
fal* far w to cpcdk i>r Ifae 
^ irttot we b«T« but ja« 
v^B^W alWwKi to sar that it flow 
fa« ne pen, is df u excellent cohtr, —a 
Hi jJMtwwr. — be- is tbo keeper of 1 
pA&nc«r4i: kimI hu not ooljr on opj 
flf VRBc.cxammin^. ukI trfTmi^, tjjc nm 
rf aanenl dale, bot wt know that be 
■■di tmt SBd »cniDeD in tbv task, 
IkliiBkwtbrraMH. 

a ivfjioj _ .___ 

Utile itnoi aad be easj tod e(ft.n:tu&l In i 
At In^tb we bare foond mie : ** cheap 1 
•ax or eight niikeasj but simptv fmir J 
We wrote « letter witli the i V 

brtweeo the iMfier prepared : .« 

hud orer it jittt a« we - - o 

fmptr, and there wv a : 
Ci«-Mi&ik as plain u tbr - ...li 

tah that tbii BUT be duac at any |vriod dj 
iKIecis wntten. The tntvntina :s reailT ei 
WiyteM iiMge> tod iaipoaaible to fail ; 
liBMBely bow, thit tbe expauiri! and ei 
CHviat naellines osoallv cnnloffed n ill I 



Capyuf. — Wc hare loii| 
^*~* whirh -trnitld toke^ 



osoally cmplnted n ill |j 
Hied by Mr. nowmu't wjy pnnable, 
md ehnp tobctitute. 



CORRESPONDENTS. 

Zx*r tuwRi <tAl for iftlrsakc 

J*y^<— We «■■■«« pOMtUy M<«w«i« 




a -Mfe «r hn. li 



^ ^ %b* «^ef% «« u aiiii a w»y 
^«^^taA m^MM c«UtlMAaAer 

^ ^ Mi^ jTlrta Mil bi a 

i«MW •*««L a H»*»*«' ^ ■* •^ . ^^ 
«.«bi« 1^ Uef yiif ^•J5*J?J*22*^ 

Mt ttWwMtv ^ a asdfcMiaw a»d ml Ml 
rMlrlm; ky Vm Mm km -nil a 
IS^MllaMiM v4 »k» «««te «f tartoln. 



j; - ^_._ . 

a &*-TWm m Mfbiai Mw n te c 
& a^Vv TCcvirvd ai» kClm, bM 
tt^M^wttN k* waatt 11 

•mW^ eartaf the wbote fMrca^ ai^ 4p arf 
fcawy l» tafca og the wd>L TW acid vvIuImI 
«<i*liBli*im afUrUifM oetoerboafm. 

Wa naUy wisb rormnocMl«wt» ««i«kM ael aua -. 
■teamat KMder/ 'rrlcad.* w wrb fawfaSMdl 
*"** ■b*rt> ,000 onuiut T«ii*n. m^ThSm 
■Hf mca^ aad Htrtljr waewiMI WeSMcMl 

» TS ^^' '^«>»fc w» dn our tawt !• aUli* all. 

M. M. I MwebH^. >—«#• " Aoti-Drr ■«<" V«4.. 1. 1 

Gvi^ttKB M Mfly as fioailbie 



C^^ TV Piaifie are rtfttHfkUf h^^hnm 



cA»/4 md htterrd, pric* 8*. /f fw«/^_ 
i^ 100 oHfimal nriUsin, and ir tmb^tuk 
ttA gy falw iyj. ' 

CMI Cbeere, (l^tttrtd), far hindme, mag 
hmi^ tht PuhfuArr, priet iOd. 



, Hooka far Ravtew, Tt%-«nlIoai vm 

^— ■ ■ *«•. *" ha ai)ilma*4 t« Uia Editor, at SI 
FrMcoC Slrett ; to llw PrloUr ; «r to Ua i*abl 
LatlMBnuii ba poat^U. 



Ptatod by D Piuacta. «, Whtt* Uocse Uav UHa bh 
£nbtlihMl evrry Saturday t»* W. BarTT*lif . 1 1 . Pal 
Raw. aad may bt had vf all lkK<kMJl«a and Nan 



THE 



MAGAZINE OF SCIENCE, 



^ixb Sfftool of arw- 



No. LXII.] 



SATURDAY, JUNE 6, 1840. 



[PucB Hd, 





METALLOCHROMY. AND SMEE'S GALVANIC BATTERY. 



[ItoALUiciivoMT u, as tbr name implies, an art 
lE||||^variiraa colorcJ rings ftud devici'a are 
^^^^^^BD the Eiirfacc ot tnctailic pUtrs. It 
^^^BBMv its rfTect upon galvaniim, snd U but 
^^^{^ of the daily occurring instances of the 
I^PathaC are liktly eventually tortisue frnm Uiiii 
IMdoa anJ votuable science. 
,1U< art in qnestiou may he made lubBorTient to 
mrnt and iJiateful deconition of moat of 
iirous steel articles which our utauufoctories 

VOL. n. 



so extenaively produce — while the proce» in so 
limple that error or fflilurc i^ impoasihlc — tlie 
variety of omaaLcnt fu great, that it nmy be oon- 
fttdcrcdendlcbs — the cost no small Miat it cmiuot be 
appreciated, and tlic effect so diHercnt from all 
other decorations that it caimot be imitated but by 
the same Deaoi. 

The whole of the art depends npon a simple 
Salvaaic experiment. The matcriali and Apparatus 
re<|uired, are a galvanic battery of some kind, of 



M.iGAZINE OF SGIEKCk 



T ■ t*- '..-■.■•- ;.''■' • .- '.".•lit*. It is immatrrial of 
¥\A? Vr-- f,;''..'/n rj.i- hat^-ry ib, any of the old 
^.n'. .-. ■": 'ffif^M will <to tiH well as those of motlern 
'ikV, *-.'• (All wircH to roiiiift't the poles, a bright 
tt'rtl pliilr, iir <jthir hri[;ht steel surfacr; a dUh 
#::i|iiil»|iol' holirmiT thi- plate : a rounii. flat, or terr 
hlit-hlly fiiiiiMM' jmiv of copper 3 or I inches o^-r. 
MMiii- Mi»Ma'tnto or MUir of Ie.U: ard j.?-:.-.! ^-il- 
phiiru- ttoiri ; thi» i"un'.:*b^?. «5 :: w:rk Lf :■:;::■»>. 

water. ?o « '.^ xii^ i w^J.^:^': «:i»ii(;n f 7:11 
haxe '. .■* i.>~— ■•: »•-■'-'* ■""''• *"^^ "°'''^ ?r;":iu:i'' 
hii- t •. :.":i-; 1* .'1 ". '1'. *■ '-■"'■* "^ *^*= ■* '■^'' -""^ 

.. n :.. .isii. xii. "-'IT 






!r "* 



IIORTL.S SICCUS; 

OR, FREPARATIOX OP bPEClMF.NS C 

rprorn M'if-\(ri,„/t, Bofnut 



COi 



l^ iij.:. z : :..f ::-„-;.. ,;> of prcpirli 
«.-:■:■• L-.-.J :t --—,:;■: ri:, 1 ;!in dtpirtJ 
M.- ^'^jr.-:;. >.r,-e...n. in L.^inlon. l 
x-L.:-*;:^ ij!.-. :-: : a mtthoJ which : 
*-r^: TiK r-. t:^4: li-. mMge : ami such n 
to :i:^'.r-i z.j riiti. ar.-i ONcoute them 
;ewi. v-i - :■: -S^-.t i:tc:i*iou5 well rew 
* -'~^*" ^-''^ai-T" to :l,e drvinj of plant:) 
ti procure the I'olL 



:« iujisssir 



V srrcf :d< Vox cf tl.<' si^p ai 

-: ijrM :':c v-.i ji.W::)^ up of tin ji!: 

1 ■-- ;ix::::7 cf tin* aad dry s; 

^ r'Ca-AizTi.:'.-; numfi^r of pitci 
"' "^ - ■■='? ': r. ir :::t:hca JiiMarc. 
• S-r- 41:1.. r'l; IciJen wcijhis 



s7fr-:^T= :: i:;T p.jitr intern 
LS «i"-iLl'i >e iMrefnllj ccUeelt 
'.•i iK-xz::i :zi i.-'wering. wjtU t 

^cTT.'c? u ro«;Vi?. and in 1 
:= -:cr_* *i:i:i be taken up. 
:r 'izi: i:^i -.3 1 tia tox well t 
Tii; Jll:: 5J:.-:i'J be cleared 



;t if .-ce ;f 
p liser 
ii«"!i r»i .-J" 

! lie :r^~ic 
r^i^is •IT' 
= :ir> :t •_: 
1.^ : li'-yr ■ : i 



i-.*ir 



i::: ::", i:hi iiK-rwirds 

;e :*'_—< l^i-es ci a cli« 

;« %l :-*r leaves a 

■*i :a an expiadei 

L 'K'^T. wLu-h a-.aj 

i::-! iij-: i>wr. by' 

tIu-.: i-e earirely t 

.:• ;-; :- t-sro of 1 

r:^: -- > '. Ll.-: : : '•:-. :»e 7 i^-.rs. Thi 

-:^ •-:" :t t -^ .i.i :^e~ ~e *r?-.-ered 

■ ■*'is :i- -'..-r- '.:: .j.-vj* w.:h tLe wt 

::> -_:; » :..- ; t_i:i: *.:■. ;1: "re jij in 

i LTLT'i-fi r.*rT_ TT :i^ sax-; s;*j.':-i. Th 

-;:-.-:»^ :ifa i-e cinr:^-^ t^'-t, :- id. aaJ 

•^ .-c zhe 5he*t of pirer irr^e-i tj its 

:.M ininc the loos* z.t-Xi ,■;' paper i 

:».':»cra them. After V-.l. .-- or t* 

:■ ■. iL* should ii? pl.u'e.1 cr. '.':.: ::r.ie of t 

'-" .■i::i-ia tiiip- til! as n:-.r." ."i^r plan 

::.'e"-...':f-ij to be pre*crTeJ. Lii c :rer. prepai 

: .ir.r..r. A layer of saod an :-cb Jeep th 

Se j-t i:.M the box. and ar'ttrwira? ot 

ris:.:?. -'ith thi' booVs pla-e*! U]:r. it. v 

.-..'l;: ?■■;■ riiiiovfd afrera SLrh^'i.r.: --uan:!! 

< r.:' "v.n rlio pqKr. to piwcri: rr.e pi; 

i-; i::^ ::« fjrru.^ All the other phn-.s ma; 

•:: :-^-; ::.^ box in the same luanner, wit 

•t:taa iach thick betweea eicli, ' 

';■.-.■ '!J \k- jtatly pressed down hr 1 

. J.vroe uf pressure, ir. SiMnc n\ia»u 

•7 th* kind of plants in the bos. 

" ,-.„? i-r:n. as the holly or fur;:e, mv 

iijx :< r.i'.iiu'.I. Jf tender and smvuUnt 

J^ii'ti; 1- Ivtter. for fear of fxtrav.iMtin(jit 

■•:;th HOuM injure the color of the plaut ; 

rijuljT oire should be taken to make a'l 

iosriv cf i»re«urc upon the expanded blo; 

y:.i:.'.-^. t!:.« tiiey may not shrivel in dryini 

•:o\ »'.:ou;d then be carefully pUced bcfor 

A :": -'.'t.' side a little raised or occasiomllv 









MAGAZINE OF SCIENCE. 



75 



0C eonymient, alternately changiiifp the 
B box to the Grr, tnicr or Ibri'o a day ; 
Dnrenietit, it may be pnt into an oren in 
mx. In two or three dayi tbe plants will 
J dry. Tlic «and should then be tnkc-n 
'common plate, and putinta a Mjuarebox. 
bnt« carefully taketi out alsOt nod removed 
of writing paper. 

toetbod of preserving plants is* froni mnch 
^ found preferable to any other, and bait 
intage attending it that can be wished ; 
(tst of them of an exrec<lingly fine natural 
|e color, a^ well in the llowera aa leaves, 
found upon trial, tJiat a different degree 

• suitable to different planta, the exact 
k of which will be easily acquired by a 
Hence, and that »ome will dry macb bet- 
ptiiers. I have oLivaya found the fewer 
ie were in the saud at a time, and the 
m Uest. tbe better itio colors were. Those 
^^wre colored flowers should br jilaced 
^■Perwise their colnra will bo injured by 
P^ltiou of the mutsture from the others. 
» are nioft fit for future examination when 
, loo»e within the paper, and if they are 
tcfy dry room and unexposed to the air, 
braserve their beauty a groat number of 

• it will he necessary to inspect tliem once 
destroy any of the small insects that may* 

Hlg them, and thij will be fuUy sufficient 
^reserration." 

bCever method tbe plants arc dried, the 
U mentioned in the last pam^aph of 
bely's account, are indlepensahle to-thclr 
pn. They may be most conveniently 
cabinet made for the pur|>0Be, with the 
io front, excepting; ouly a shallow 
m of each — placing tlic oprcieaof 
er, Bad keeping each chub separate. 




IBtNDING AND POUSlIINa 
LBNSES. 

Uiijig is to fix upon the proper aperture, 
and focal distance of the ^lua : a piece 
pppCT i» ifaeu takea* and, with compasses 
the focal disuncc, supposing the gltuia is 
to be convex on buth sides, and two 
|ch a lilUc larger than the intended 
f the glass, are then struck ; but if the 
"be fiat on une side, the compasses are 
I opened tu hiilf the distnnco of the fucus. 
^per lA iJieo fUcd away frum the outaide 
uose arches, and from the inside of the 
which moans two guages arc formed, — 
DTSS and the other concave. 
reaUr plates of brass, half an inch 
ban i}ie LuicDdcd glasses, and abuui a 
in inch In thickness, are then taken, and 
Irs are soldered upon a cylinder of lead 
Be diameter, about an inch hiffh. One 
mU, as ihey ore called, is fixed upon a 
tnd turned so as to correspond with. 
tfS; And the other to correspond 
. The two tools nrc then to 
with tiie linest flour emery, 
•sactly CQiucide. If the focal 
short, the plates, before they are 
_ tho lead, shuutd bo hammered, as 
oou be douc, iulo the proper fuctn. 



If the lens is not for achromatio instxumcnU, 
glass of a straw- color, whose dispersiva power is 
as small as poasible, is chosen, which has the two 
surfaces parallel ; and. by means of acisHors or 
pincen, it is cut into a circle, the edge smuothed 
by n common grindstone, and it is fixed by means 
of pitch tu a wuudeu handle of leaa dianieu-x than 
the glass, and about an inch high, so that Ihu 
centre of the handle may exactly coincide with 
the ccniro of tlic ^\%aB. If the intended focal 
dUlance is very small, the surface of the gloss ia 
gromui on ihc grindstone, so as to suit the gtiage 
as far as possible. 

The glass being thus prepared, and supposing 
the lens intended to be convex, which is the most 
common fonn, it is llicn ground willi Aue emerr 
npon th« coooav* tool, which i« lo be firmly llxcd 
to a table or bencli, and tho glass wrought upon il 
with cLicttlar strokes, so tJiai its centre may nevor 
pass beyond the edges of the tool. AAor crory 
circular turn, two or tliroe cross turus along tho 
diameter of tho tool, in differcut dlrcclious aro 
given. 

When tho glass haa got into its proper shape, 
and tuuches tho toul iu every part of its surface, 
which niny be easily known by inspection, the 
cmury is to be washed away, and finer kinds sab- 
stituted, unlU all the scratches and roughocsM8 
are worn down. Thoso that remain afler tho 
finest emery has been used, arc taken away, and 
even a sligut polish piren tu the glass, by gzindiug 
il with p4umd(d pumice stone. During all this 
operation of grindinu, the convex tod, at Ihc end 
of every five minutes, is ground for a few seco&ds 
upon the concave tool , in order to proserre the 
proper curvuliirp. The glnas is then acpAra-lcd 
iVom tho handle by a knite, tho pitch leniovcii by 
rubbini; il «ilh n little oil, the already gruund aide 
tixcd npon the handle, and the other side ground 
and nntshod in the same manner. 

To form concave glasses, the convex tool is used 
in the same manner aa the concave tool is used for 
convex glasses. 

Some persons, for concaro glaascs, use leaden 
wheels, having the same radius as the curvature of 
the glass, and with ihelr circumference of the 
same convexity as the glass is lo be concave. 
These whechi being fixed upon a lalho, the gbisa 
is held steadily in tho hand, and ground upon, 
them with emery. For common purposes, convex 
glasses are grouud by fixing the concave tool upon 
the lathe, and applying in the same mr.niicr the 
glass to it. Bui this manner uf grinding will not 
do for glosses when they are lo be employed in iho 
best kind of optical iustrumenls. . 

When the glass is brought by these. methods 
lo the proper form, the next and by far the most 
dlfhcHlt part of the operation U to give tlic lenses 
a fiiic polish. 

The best way of polishing these glasses, although 
not the simplest way of doing it. is, supposing tho 
lens to bo poti.thcd is a convex lens, to rover the 
concavo tool wilh a layer of pilch, horilcncd by 
being melted wilh a Utile rosin. This covering of 
pitch should be laid on to about tho thickness of 
one-fifteenth part of an inch. Then a piece of ihin 
writing-paper is to bo taken, and pressed upon tho 
surface of the pitch by means of tho convex tool ; 
but the paper is to be pulled quickly from the pilch 
before it has begun lo adhere lo it, whose surfccc 
is then lo be examined. If tbe suifoco of Ihc 
pilch is every where marked witli ihc lines of the 
paper, by tins having coiucidcil ca.uclly wilh (be 
surface of the convex tool, ihcn it will bu Uuly 



76 



MAGAZINE OF SCIENCE. 



I 



spherical ; but U* the marks of the paper do not 
ftjipcHr vn every part of the pitch, the operation 
mutt be repcatfd until tlio bed uf pitch is accu- 
rately s()ti'.Ttcal. If any pAper Micks and rcninins 
on Ihn Hurfiice of Lho pitch, it must be rcmoTcd by 
«oap and water. 

'the bed of pitch, or poILjhcr. being thua pre- 
pared, tho glut is to bo wrought upon it by oir- 
cuUt and cross strokes, alternately taken, either 
along wiUi putty powdi>r, or colcolhar of vitriol 
and watrr, until it hiis rei'etved a good polish ou 
both sitJc'tt. 

The polifthing proceeds very slowly at first, but 
when tJie bod of pilch becomes warm by friction, 
it proceeds rapidly. When llxc polishing is nearly 
iinJ«liLd, no more powder or water should be put 
upon the pilch, which Uiould be kept wami by 
breathing on it; and if at any time tho glass moves 
iLiflicuUIy, lu consequence of its adhereacs to the 
tool, it should immediately be removed, lest it 
pfaonld spoU the regular sphciicity of the pitch. 
Sometiuirs particles of dust, or fragments of pitch, 
pet in bi'twt't-n the k'™** ^ud the bed of pilch, 
which U immediately sliown by the very unpleasant 
mnniicr in which lite fiUa^ works; in this rase, 
the polidhcr niunt be intilanlly stopped, and the 
luuJiisss rvmovod with great care, by washing 
^ulh tho glass and tho bed of pitch, as otherwise 
th* rIsmi will be scralihcd, and the bed of pitch 
lUsIl matcrialU injured. 

There is. ns has benii ulrcndy suggested, a more 
•imple way of .polirtltine. by covering the layer of 
Jtitrli with a pteci* of cloth, aud givuig it a spheri- 
cal form by pressing it with the convex tool when 
tho pitch is warm. The glass is then polished. 
Upon till- mirfiire of tho cloth, with putty or colco- 
thar u( vitriol, until its surface is sulficimtly 
•moMth. The opcrntion of poltahing by ihiit method 
la slower than with pilch alone, but still it is Uie 
best fiT thi>«i? whn have had Hltlo or no experience 
;in polishing, and who, in consrquenro of this want 
of ptaclicc, would be apt to injure tho sphericity 
of the glass, by attempting to polish it on a bud of 
pilch. 

Atihough colcothar of vitriol is mostly used for 
pdlinhiiig glass, there is one inconvenience which 
attcnda jtv use : tltal often, trom not being suffi- 
ciently wojihed. it contains a portion of undecom- 
fiisrd aiilphalo of i/OD. Now, when this portion 
uf rojipcnu is dissolved hv the water, it leaves a 
yidluMi oLhrc, whiLli readily pcnetralfs the glass, 
Atid luims an incrustation upon It.s aurfare, and 
gives it a dull and yellow tinge, which is coni- 
Biunicated to the optical intbges seen through it. 



DOMESTIC GEEENilCUSES AND 
FEKXEKIES. 

fUtiumed from pa^e 34, and conctitded.J 

T)\K U'ms coTiSiiiuXe a.n order of plants different 
from all others — not bearing flowers, they are rc- 
pitfVcd fium Uic usual characters of those plauts 
with whii^h we are best acquainled, aud yet their 
fin<f and delicate foliage — vivid gieen color — aud 
tjrgnnt habit, exempt them from that neglect 
whlt^h flowctless planU usually meet with. 

t»ne species, " The Brake" as it is called, which 

ilpronds iUclf in much profusion overall our sandy 

pommotts. will give us a good idea of tho general 

lUuolnre of the whole. The root is black, crcep- 

luid shows uut at iolctvals xathor stout fibres. 



The frond, by wliich tsrm is meant the wholt 
the plant which is above the ground, except Ihi 
fruit, is at first carefully and beautifully rolled s^ 
in a manner similar to n watch Fpriug. Wkis 
beginning to grow, it gradually uncoils itself op- 
wards, and the side branches m like manner iiv 
aftei wards unfolded, until the plant has attuBcd 
its usual size. In & very short time after the ex- 
pansion of the frond, various spoils moAlly of i 
white color, show themselves in the uiider suj ' 
of different parts; these gradually increase, 
soon show lhcmselVL*a to be a coUecliou of 
or rather seed vessels — sometimes covered wit 
membrane, at other times without this membi 
or indusium, and according to thi^t circnmstanc 
and according to tho position of the sori 
braoL-hes of seed vessels, so the ferns are diri^ 
into genera or families. 

The thecff or seed-vessels are of thn most 
mirablo formation, and under the microscope 
seen to have a curious and wonderful apj 
to scatter the seeds with which they are i 
In an early slate the theca w round, thin, 
niahcd with a finely knotted or joinied rii 
extends from one end to the othw. WI 
the ring bt'comca elastic, the theca tender, 
length it bursts asunder and continues to 
backwards and forwards, until every seed 
been thrown out. — The following cut shows 
manner of lome apeciofl bearing their fruit,- 
also the manner of its being scattered. 




A are two species of foreign ferns, one 
round sori, Polypodium aureuD\; the other 
lung sori, .\spleuiuiu. 13 is a thcca or seed vi 
C the seed from it. O, a speries of (am 
which the fruculied portion is distinct from 
barren frond. — This is the Adder's tongue, a 
not uncommon in some ports uf Kngloud iu 
postures. 

The soil which suits best this tribe of planl 
a sandy hog earth, — such as is found m the wcti 
pan ol'boygy commons mixed with white sand 
that which is bettt adapted for the genernt soil ol 
fern house. The plants will bear rcnioral sri 
little injury in the spring of the year; even in 
summer ihcy may be removed with safety, provic 
they arc kept ctmatantly moist for some days 
their transplunlation ; and as this constant 
moisture is a necessary cousequenoe of the 
tictilar mode of cultivation here recomaioD< 
little difficulty or danger La likely to accrue. 

Most of the damper parts uf Great Britain 
duce more or less species of ferns, and soiztc 
Uiem of the greatest beauty aud fully oqu 
most of forcigu growth. Some speoi* 
naturally upon walls,— others in the dtt 
bogs. — others again among the rocks uf m< 
ous countries. One elegant little specu 
menophytlum tunbrigcnse,) covers the hi^^ 
at Tunbridgo. Three other kinds aro 
common on walls, (Asplenium adiantum 
aspleuium trichomanes and asplenium mta 
ria,) one or other of them may be found on nt< 
of tho old churohca and walls in England, 



MAGAZ1N£ OF SCIENCE. 



77 



npltf, at Twickenham, Ham, Richmond, 
eowich, Charlton, Cobham, &c. &c. Diffcront 
M kinds ue no lew abundant, in the damper 
bfif woods and commDiis. Aspiduini ti'ax-mns 
Miaduit aimusl orcry whcru in the hed^-row 
b«9) where the root may bo dry in the winter, 
IT therefore in tiie ditches which iutcrtect 
sb; land. Scolopcndrium ralg^are, Blcchnum 
■ale, Aiplenium rilix-focmina, or Lady Peru, 
Polypoditun nilgarr, are no less abundant in 
yj places. The latter ^ows mostly, either in 
trees or on the summit of high heilee banks. 
fonncrr kinds in wet places, as WoTler Suutt 
arks truly. 



I tUalens MieaaMi, 
Wbfrv ihe mormlnfoew llti longnt. 



Whorv Uifl fauuUiD itUalens 



Tbcr« Ihc Lady Fera grows •trongrvt-'* 

bout Loudon the principal stations of these 
I, arc the valleys of Wimbledon Common, 
■ko around the well or spring near Caesar's 

S Another station is around Twickenham. 
Countess Paulet's wall, and the ditches 
Laae-bridge, and onwards through Wilton, 
y of the Ikuies near Brentford, Cacnwood necr 
£i|:ato. and particularly Hampstead Heath, — 
lad tho little pools of water in the marshy 
Ed at the back of Jack Straw's Castle. In 
eoontry wc may mention the following situa- 
ik where many kinds arc to be found.— Rocks 
s-yri^npy ground around Tunbridge, ditto 
'. ing and Kycgatc, ditto around Bristol. 
itocksnearSheOicld. generally in simi- 
aiwLUijus throughout Derbyshire, Lancashire, 
Cheshire ; mouutaiiious parts of the lake 
itiM. IngU'borough and Cumberland is par- 
llriy rich in ferns, so is BcrwickAbire. The 
Ui and Scottish mountains and woods yield 
I own peculiar kindd, some of them found no- 
ne else in Briuiu; while Ireland is equally 
loctiTc of numerous species, particuhirty in 
Home and Cunnamara mountains, Powcr's- 
rt waterfall, and the district arouud Killarucy. 
ia liat might be extended to an almost un- 
ied dcgTee« there being scarcely a fertile valley 
r a rocky mountain — a shaded hedge-row. or a 
pidatcd building throughout ihe whole king- 
I, where some species or other does not 
tiib: of coarse ditferent kin<U in diHercnl 
ws; thus. alUiough some may be generally 
iSbuted from North to South, yet tlie ferns 
dh abound in one country may be, and usually 
oompaxativcly tare in other and distant places. 
torn the above it may be supposed thiit Fern- 
I or Domestic Greenhouses ore adapted for 
growth of only the piUticular tribe of plants 
i descnbud. such a supposition is extremely 
flcous: the hot and damp atmosphere williiu 
D is particularly condoaive to the rapid growth 
oUsge iu goueral, thus moat plants will grow 
e luxuriantly than inordinary situations, even 
bnUent vegetables, the genera Cactus, Sta- 
IpRMala, Aloe and others may bo thus 
PStd with complete success. Hcallis, £ha- 
, and different plants of a similar rigid charac- 
trcm to fl"ur«ih well; indeed, it may be said 
nd greenhouse plants in general 
[imate adapted to their habits. 
. iaiji lam.'pica thu3 treated becomes a 
ildid plant. — and that remarkable and curious 
^ the Orcliideous plants, which in the woods 
Sumatra, and otlicr tropical regions, 
nuMt brilliant festoons from tree to tree. 
of tho chancterherc alluded to be 



attached to bits of bark, the Bbroua parts of cocoa 
nut husks, or planted in baskets hlted with moss — 
when ihey will grow luxuriaully, sustained merely 
by the conslant moisture of the air, throwing out 
at the proper soasou their branches of singular, 
beautiful, and often fragrant flowers. 



SAFFLOWER- 

rtNK SAITCKKfl» BOUOB, CHtMA BOVGB DOOKSi 
AMD CHltTA LAK.K. 

Sawlowsb, bastard saffron, or dyers' laSronf la 
the flower of a species of carfhamitH, being the car- 
thnmf*M tinctorivt of Linnicus, who places it in hia 
order tryngentnia polygaiHia mqualU, while Jussieu 
orraages it in bis order of composite. 

It is an annual plant, growing naturally ii»Eg^t. 
but which is also cultivated for the use of dyers, in 
the Bast Indies, and several of the warmer countries 
in Europe. Its stem is upright, firm, smooth, whi- 
tish, two or three feet high, divided at top into 
several branches, garnished with simple, undivided 
leaves, of an oval form, pointed, and edged with 
small spines. Eoch of these branches has at the 
top a Urge tlower, conijMned of several florets, 
slightly cut in five jogs, all of which are furnished 
both with stamens and pistils. These flowers are 
of a fine red color. 

Safflower is collected for use as soon as it has 
blown, and is dried in a shady, dry place. If left 
until fully blown, It loses much of its tine color, 
and thin lowers the value very greatly. When the 
safQower is of a bad color, it shows that it wasooU 
lected in bad weather, or was badly dried, and that 
the coloring matter has by these means been spoiled. 

Safflower is much used in dying. It contains 
two kinds of coloring matter, one of a reddish 
yellow color, which is not used, because it only 
dyes dull shades of color. The other coloring mat- 
ter contained in safflower. Is of a beautiful rose red, 
and is capable of dying every shade, from the 
palest rose even to a cherry red. 

The first coloring matter is very easily dissolred 
in cold water ; but the second, being of a reainoua 
nature, it) not soluble in that lit|uid. In eonsequcoce 
of this difference, they may be separated from ona 
another by washing the safilower tied in a sack, laid 
in a trough, and trod by a man, while a slender 
stream of water passes through the trough, in order 
to wash away the yellow coloring matter. Molten 
the water with which It Is washed no longer be- 
comes colored, the washing is discontinued, and the 
safflower, if not wanted for use, is made into caken. 
under the name of stripped safflower. These cakes 
or the loose stripped satllower, are then soaked in a 
weak solution of barilla in water, (generally 6 lb. 
of barilla to the hundred weight of safflower ; the 
bath, (as the dyers term the infusion, ) speedflj 
becomes colored of a deep reddish yellow. 

As soon as the soaking of the stripped safflower in 
this bath is supposed to have been continued a suf- 
ficient time, it is strained, and carded cotton la 
dipp<:d in it, and a sufficient quantity of acid ia 
added, to completely saturate the alkali that was 
employed. Citron juice ia usually employed for an 
acid, because it renders the colors more lively than 
other acids. The carbonic acid gns, or fixed air, 
which is disengaged during this saturation of the 
barilla, produces an effervescence, and care must 
therefore be taken tliat the liquor docb not run over 



MAGAZINE OF SCIENCE. 



the nlgeof the reitel ; and it is proper to idd tba 
citron jvice, or citric sctd, either it its bravn or 
pare white state, in small portions. 

The coloKng matter eatrscted from the Mfflover 
keing only kq>t dissolved by the help of the alkali. 
is of cotueqneDce tepanited in propurtiou as the 
aikalt becomes saturated with the acid ; but instead 
of settling on the sides or bottum of the vessel, it 
fixes in preferfuce upon the cotton, with which it 
Lab what is commonly called an affinity. 

It is not possible to separate in the first wuhing 
the whole of the yellow coloring matter : the part 
whicli remains is taken up by the Usrilla, and ren- 
ders the shade of color given to the cotton rather 
doll : but this is easily got rid of by repeated 
washings. When it is well washed, it is soaked 
again in a aolation of barilla, and thus a bath of 
the perfectly pure rcsioous red coloring matter is 
obtained. In order to dye with this pure bath, the 
stuff to be dyed is soaked in the bath, and, as in 
the preparation, a nufticicnt quantity of citron juice, 
citric acid, or tartaric acid, is to be added. 

If it be wishe<l to obtain the coloring matter 
aeparate, as in the pink aaacers nf thtry are called, 
the same operations are performed, with only this 
difference, that nothing upon which the coloring 
matter may fix should be put into tlie bath. By 
degrees there settles a very line powder, the liquor 
is then decanted off^ the settling washed, and dis- 
tributed upon saucers, where as it dries it acquires 
a coppery tinge, which exhibits a reflection similar 
to that of Spanish Hies. The rose red color is 
produced as soon as this is wetted. 

Thin coloring matter, mixed with French chalk, 
reduced to a very fine powder by means of scraping 
tfafi chalk with Dutch rtLshes, is the cosmetic called 
vegetable rouge, used by the higher classes of 
females, especially in foreign countries, to paint 
their cheeks. 

The Chinese, instead of saucers, use a folded 
piece of card, covered with Indian paj>cr, to spread 
the red coloring matter upon ; a Auger being welted, 
nibs off the color, which is u much neater metltod 
for the l&dics, than the saucers of the European 
perfumers. 

The resinous matter may also be preserved ia a 
mai«, by merely drying the precipitate ; it is then 
rolled Tndiun, or China lake. It does not com- 
municate any color to water, hut produces a beaatt- 
fut red tincture when spirits of wine are poured 
upon it. 

When safllower is used to dye sUk of a poppy or 
flame color, the silk most not be alumed. and a 
slight annatto ground is finit given to it. For a 
pale carnation, a little soap is added to the bath. 
All saftlowcr baths are made with cold water, and 
used cold, as heat sjMils them. 

METHOD OF PERMANENTLY FIXING. EN- 
GRAVING, AND PKlNTlNCi FROM 
DAGUERREOTYPE PICTURES. 

BY DR. HERHHS. 

Reod bfjbre the Imperial Society qf Vienna. 

It was announced in the Vienna Gazette of the 
18tb of April lost, that 1 had succeeded in discover* 
ing a method, by which I wns enabled both perma- 
nently to fix the pictures produced by the nieilimlof 
Daguerrc, and to render them available to all the 
purposes of etchings upon copper, steel, ^(C■, from 
which copies might be struck off to any extent, as iu 



the caae of ordinarr engraved prodnctloiMi lod it 
was stated in the same newspaper, that I profttwl 
bringing my discovery immediately before t^ 

public. 

As a member of diis distinguished Society I OW' 
aider it ny duty, first, to make known to this learned 
body a discovery which creates to much hope, and 
which promises so great a benefit to the nrta aatl 
sciences. The well known expenses and difficulties 
attendant on the publication of an extcDsire work, 
requiring engravings as illutilrntiuns. led me in the 
first instance to hope, that I might be enabled to 
render the discovery of Dagnerre avsiilable, by 
improvements, to represent and fix the otjeett 
necessary to ray work ; and the first view of an 
heliograph*^ picture aroused in me the desire also* 
to represent in the same manner microscopic obfMtii 
although attempts with the strongest lajBpfi^rt M 
produce engravings ur etchings had been iiiiiini iiMi 
fnl, and ^e idea abandoned as hopdcH, onifl 
revived by a sight of the hydro-oxygen gas Mri* 
croscope of Mr. Schoh, of Berlin, an 
whidi in its power and clearness Has nerer 
been equalled or even approached. On the ^T^ 
of February last. 1 had iho honor of Uying h^4im 
this learned body, the results of the ui 
vestigations of my distinguished coUeagoc 
de Kttingsbausen and myself upon thi> 
and the perfectly sucoesaful experiments vi 
prepared tlirough the proceu of photogrfij 
microscopic objects. Many spccimnef^ n( f!(^ 
resultsof our researches and niccesaful atumpu w 
employ photography for scientific and uaeful pur- 
poses are now placed before you for examination* 
Through this new method the Daguerreotype Is 
rendered more exteorively available for scieotite 
uses. Every object which is discernible 
with clearness can, for the future, through 
of the iodined silver plates, be minutely 
true to Nature, (for she is herself the 
copied with the minutest exactness. 

In a Petersburg newspaper of March last, 
saw on account of some attempts to 
Daguerreotype process into general use. In 
meantime, M. Dagiierre had declared, before th4 
Institute of Pariij, the complete failure of ail hia 
■^mpts. by means of etching, to obtain the impraa- 
■ion even of a single copy. 

The experiments at St. Petersburg, and the hoM 
of eventual success, urged me to attnupl to mau 
some use of the Daguerreotype pictures^ asd I 
bq^an, at the commencement of iliis month, my 
series of experiments. Without recapitulatiug sU 
these, in which I was assisted with cordial ual b; 
M. Francis Kratochuila, (a gentlemen in the etn 
ploy of GoTcrnmeot,) and by M. Schub, ^« ' 
at my disposal an immense number of Dag > 
plates, — and, before I come to an expUnatinn oi um 
proceis, by which 1 render these Doguerrrotypa 
pictures permanent and capable of further use,—' 
I consider it necessary to h&y before this leuasA 
Uudy the following observations : — 

1st, With the copper plates, as naed at p teaeu t 
in the Daguerreotype process, we can effe^ <nly 
the permanently fixing, never the etching and priflU 
ing of copies therefrom. 

2nd, For the hcliographic etching it is nf rrmry 
that the picture be produced with the required ia< 
tensity, upon pure chemical silver plates. 

^)rd. The etching of the Dagurrrrotype pictvrt 
is produced through the ioducncc of nitric Acidr ll 
be explained hereafter. 




MAGAZINE OF SCIENCE. 



4 tJt, For Uie pcrmtamtlj fixing of the Dafpierreo- 
tfpe iroprcMton, a galvBoie power is neccftsarjr. 

5tht For the changing of the Daguerreotype pic* 
tare into a deep metal etching, bo ai to be used aa 
• aeuu of printing, the cbemical prooess of etching 
u of iteelf iufiictent. 

My newty-tliacovered method of managing the 
Hl^giMrreotjpe pictares, may be divided into two 



I at. That of permanently fixing the detigo. 
2ac), The changing of the design, when once per- 
Biuieatty Axed, into an etcliing upon the plate. 

The method of perinftnentlT fixing the Daguerreo- 
type pietnre with a transparent metal coating, con- 
list* iu the fullowiug process :^ 

I take the pieture5 produced in the usual manner, 

by tba t^aguerreotype process, bold them for some 

MfamCM over a moderately -wormed nitric acid vapor, 

or aCcAin, and then lay Uiem in nitric acid of 60 to 

Ct^ (Fah.,) iu which a considcrAble quantity of 

aopper ot silver, or both together, has bp^en pre- 

dvalrdiwolved. Shortly after being placed therein, 

• pffVOipitate of metal is formed, and can now be 

QUfeo to what degree of tnteniity I desire. ] tlieo 

tihc the heliogtaphic picture coated witli metal, 

pUce ii in water, clean it, dry it, polish it with 

dulk or magoeaia and a dry cloth or aoft leather. 

this procesa, the coating will become clean, 

and tniTiflparent, lo that the picture can again 

ity teen. The greatest core and attention arc 

lired Id preparing the Daguerreotype impressions 

led lo be printed from. The picture must be 

freed from iodine, and prepared upon a 

the most chemically pure silver. 

t the production of this picture should be 

cdtiia of sticcecding, according to the experimenU 

of M. Kratocbwila, it is necciinary to unite a silver 

ff& a copper plate ; while upon other occasloiMf 

■itttoat being able to explain the reason, deep 

tftUags or impreaaiuus are produced, wicltout the 

lirtiiH t] of the copper plate, upon pure silver 

The plate should now.apon tlie spot where the scld 
M;;bt not to have dropped, be varnished ; then held 
Iff one or two minutes over a weak warm vapou r or 
I, from of? to lOO^ (Fah.), of nitric acid, and 
solution of gum arable^ of the consistence 
must be poured over it, and it must be 
» bori2ontal position, with the impression 
for some minutes. Then place the 
aris of a kiud of double pincerif (whose 
protected by a crnting of asphatC or hard 
in nitric acid at 60' (Fah.) Let the coat- 
gnu slowly melt off or disappear, and com- 
now to add, though carefully and gradually, 
a distance from the picture, a solution of 
«cid, of from 80 to 100" (Fah.,) for tlic pur- 
>f deepening qf increasing the etching power 
of the ftolutian. After the acid bu arrived at 68 
la 70' (Fall.), and gives off a pectiliarly biting 
vipoor, whirh powerfully aflects the sense of smcU- 
;, the meul t>ecome8 softened, aod then generally 
procew commences of changing the shadow 
the plate into a deep engraviji| or etching, 
is the derinivt^r moment, and upon it must be 
Nslowed the greatest attention. The best method 
OTpronng if the »v\d be ttrong enough, is to apply 
• drop of the acid in which the plate now lies to 
noUier place : if the acid make no impression, it 
course, ncce^i&ary to continue adding nitric 
howcTer,'it corrode too deeply, then it is 
tQ add water, the acid being too strong. 



The greatest attcntioo must be bestowed upon thla 
procesa. If the acid has been too potent, a fer- 
mcntnliun of while froth will cover the whole 
picture, and thus not alone tlie surface of the pic- 
ture but also the whole surface of the plate, wiU 
quickly be corrofied. When, by a pro|>er strength 
of the etching powers of the acid, a. soft aod ex> 
prcBsive outline of the picture shall be produced, 
then may we hope to finitih the undertaking favor- 
ably. We have now only to guard against an ilU 
mejisured division of the acid, and the avoidance of 
a precipitate. To attain this end, I frequently lift 
the plate out of the fluid, taking care that the 
etching power shall be directed to 'whatever part of 
the place it may hnve worked the lea#t, and seek 
to avoid the hubbies and precipitate by o gentle 
movement of the acid. 

In tilts manner, the process can He continued to 
the proper points of stren^h and clearness of eteh' 
ing required upon the plates from which it is pro- 
posed to print. I believe that a man of talent, who 
might be interested with this art of etching, and 
who had acquired a certain degrci; of dexterity in 
preparing for it, would very soon arrive at the 
greatest clearness and perfection ; and, from my 
experience, 1 consider that he would soon be able 
to simplify the whole process. 1 have tried very 
often to omit the steaming and the gum orobic, but 
the result was not satisfactory, or the picture very 
Boon after was entirely destroyed, so that I was 
compelled again to hove recoorse to tliem. 

The task which I have undertaken is now fiilly 
performed, by pladng in the liands of this learned 
body my method of etching and printing from the 
Daguerreotype plates^ vihiiA information, being 
united to the knowledge and mwhinical experience 
wealready possess, and published to the world, may 
open a road to extensive improvement in the arts 
and sciences. By thus laying open my statement to 
the scientific wurld, I hope to prove my devotion to 
the arts and sciences, which can end only with my 
life. — AtAeaaum, • 



MANUFACTURE OP STARCH. 

Potatoe Staroh^ or Bngliah Arrow Root. — [i 
presents very varied forms, and no other known 
kind acqtttrcs so large & diic. Whun first obtained 
from Uu: urguns of the plant, it exhibits concentric 
wrinkles on its surface which disappear 05 it dries. 
The largest grains arc about .0049 of an inch in 
size. The most common size is from .004 tu .0015. 
They are oval, contracted in tlio middle like the 
cocoon of ihc Bllkwomi, gibbons, obscurely tri- 
angular, or rounded, and the smallest ure spherical. 
The potatoe is the only plant whoso Lcula is 
used for culinary purposes, as it can be obl*ined 
at a cheaper mte than anv other. To extract it, 
the tuberclea are washed, and »crubbe<l, aAer 
which, they are rasped under a stream of water, 
which carries the rasping*! to a sieve, through 
whoBe meshes the fecula alone passes into a rcsscl 
placed below. When the operation is finished, 
the water in poured off, and the fecula is repeatedly 
washed until (he water carries otf no soluble 
matter ; after which it is dried in the sun or in a 
^tovc. This fecula thon has the appearance of an 
impalpable crystalline powder, having a while 
color with a slight blucish lingo. The grains arc 
less altered iu this than iu uny other variety of 
fecula. 



80 



MAGAZINE OF SCIENCE, 



Whtat Storck, or Hatr i*ounUr.-^Thc Urircst 
^ins of this do not Kencrall^ exceed .CMJ2 ut* xn 
inth\ntnze\ they arc spherical, nnd uloiif;>vi(h 
them wc SCO empiy and torn membrnDCb re^uluiig 
trom the bruiaiii^ of the grains by the milt. 'I'hoy 
arc much smaller, rounder, and belter preserrua 
when they arv extracted from the grain while it in 
precaish and not ripened on the BUiWt. ll u ex- 
tracted in the foUv^iug manner for the n»c of 
laundresses, vrho prefer the surch of it tu any 
other fur dressing tine linen : — The sljiri-h-makere 
place in large vats the wheat roughly ground, and 
without separaliDg the hran, and employing even 
tho refuse of Aour and damaged ^rbeat. Tbey 
diffuse the fahna in a certain quaniiiy of walcr, 
adding a little " sour/' which is ihc nroduct of a 
preceding operation. The sugar and the gluten 
which the furina contains speedily act on each 
ulticr, and produce, at first, carbonic acid and al> 
cohot, and afterwards acetic acid, which completes 
tho solution of the gluten. It is this solution 
which is called tho "Sour" or "Fat Water.'* 
It is muddy and viscid. According to Vauquclm. 
it contains acutic acid, alcohol, acetate of ammonia, 
phosphate of lime, and gluten. After having 
wasltod the deposit by decantation, it is difTused in 
wnter, and thrown on a hair*aievc placed over a 
tliu. Tho coarsest of the bran remains on the 
sieve. The fecnUi and the 6ner part of the bran 
pass through, and vuhside together. This deposit 
IS again mixed with water ; and, on allowing it to 
rest, the fecula, being the heavier, is first deposited, 
and the bran forms the upper layer of the preci- 
pitate. A portion of this is taken oil with a nhovol, 
and by repeatedly washing the upper part of tho 
remaining mass additional portions are removed. 
The residue is mixed with water, and passed 
through a sieve made of silk. Thus a fresh por> 
tion of iho bran is got rid of, and nothing more is 
required, but to let the fecula subside, and wash 
it, in order to obtain It pure. Lastly, it is dried by 
taking it up iu wicker baakots, havini; a loo&o linen 
lining, uid turning it out. of tlicsc nmuMs on an 
area coated with plaster. The blocks of starch 
thus formed are broken down by the hand, their 
fragments are exposed for some days to tho air, 
their surface is amoollicd, and they are carried to 
the stove to be perfectly dried. Tho lumps of 
staroh thus obtained have a certain regularity of 
shape, which seems to indicate a nido \;rystttUiza- 
tion ; but it proceeds only from the action of the 
water which cracks the mojis in draining out of iL 
Thtsst.irch is always loss friable than that of the 
potattiG, in conHequencG of a certain portion of 
glim and augnr which its particles, as they subside, 
envelope among then). It in suitable enough for 
the extraction vf fecula from all the vegetable or- 
gans which contain gluten, from barley for ex- 
ample, which the atarch-makcn use as well ta 
wheat. 



MISCELLANIES. 

Ijiuidariet* fVnrh.^Tht wheel made use of by 
the IlimliHis fnr thi' cttititigaad polishing uf pre* 
cimis «t»nt>A, is com[>ostd of one port of gum lac, 
and two purtAiif {Kiw<)er«<I emery (or eonundrum.) 
TbeeutLn powder is first henicd in an earthea 
ve(i«.-l. an(l when the heat is tnilhcicut to melt the 
gum, it is added in small portions, stirring (be 
whole about to promote Iho union. The ]>aste 
thus made is beaten with a pestle on a smooth 



slab of stone ; ofterwmrds nlled on a stick sad 
re'h<?atcd several time«. The miiturr bfliji|; 
tmiform, it is taken from the slick, ami laid cm « 
stont' table previotislv covered with the fiao eiOMV 
powder, where ii is ftaitcned into th« shape eft 
wheel bv an iron rolling pin. llie wheel is (bra 
polislied bv an iron plate and emery powder, aad 
a hole muae tlirough the middle for an aals by s 
hot rod of iron. When mounted it is fixed wtih 
its axis in a horizontal dlrrction, and tlie work* 
man causes it to revolve by means of a spring bflur 
held in his right hand^ while he holds tlic sU»ne to 
b«cut Id his left, ocoostonallv apjdwng emery and 
water. The ]>olishing bo cffccLi by Itradcn wbrcb 
and a fine powder. 

Horlicuttmrt, — D. Powcl, Esq., of Loughtoft. 
Essex, recommendit the following method of mw 
curing the scion when fitted to the ttiock in 
grafting :— Spread the wax iu a melted stst» 
evenly on Bbeets of moderately tliin brown papsr, 
and when cold cat it into alips about ^ of an iodi 
wide i warm one of these slips wiUi the brwd^ 
and bind it round the stock and scion, presshnf ff* 
gently with the baud, when it will be ^ 
adhere so closely as totally to excladc bi>t 
moisture. I'he wax may be prepared by 
together 1 lb. ttf pitch, 1 lit. of rcstn, <^ lli 

wax, ^ ib. of h«^fs-lard, aud ^ lb. u( tu:, 

By placing the composition in an earthen psa 
over boiling water, it may be kept in ituch a stali^ 
of fluidity as to be easily spread ou tJic paper wtlk 
a brush. 



CORRESPONDENTS. 

W. It. B — Piilt)t «iiil varnith mkv It* r*IDOT*<} ' 

paste of peulatb. iikiickiimo. stiif vttiltr. Itlil oi 
L. M. K, — Til* ioitrunifnt y'>u allud* Iu U a Bu 

Irnmvler. Ttip uu? nT U will bt viplalDod Whe- 

U> UiAl iMrl uf the fuLject. 
AuiiKk ram V^ftMiiH Abould be Qnt pnuD<li»1. th- 

to *<iak Tor «omo dayi In b httlv tplrtU <ir ' 

«rti<maril*ul«l oil, sad boil It up fttuMly, Snil u 

b«At ■■ pr>»ibls. 
Stul Bar* cut maile and ms2n«Ui«d by a panon wUo Utu 

Kl No. :i. Bull Oourl, TooUy SttvvL 
W. M. — 'llio iolubon nqulMB %a t>e mi-tir<U*(l lt> 1|¥>.it. 
J. O. C— llie ctmcBt ta ipsika ' 

Ituhluir; whicli may Im boodtil At * 

S. KimK, — II mty be ))OU||kt of Mr. ^'-Lurmiui. m lbs 
Strand : w« brliave Ui« |)nc« is mm pitiiP«- 

SoDA Watik U nut Klteted by «g«.— Oimcr bc«r ^»^ It mtiX, 
bontvfr. like dder. kf>cp n long Uiii« l' w»tt made. 

G. C— o. — Sorely he csuuotcxiM.'ct lu to giv cLrvftlflW *■ 
cleauog nintlon*^ 



(C^ The Public are rfupei-^Uly nf/bmw^ Ulif 
Vot. I, ^ this Mngarine it hmc ready, frotmd fa 
cloth 4md lettered, price S#, . // evmimnt 
^f 200 oriffhmi articten, and it rmleiiithtd 

230 cnffravingt^ 

Cloth Cnt^rit, (fettered), for Mndin§, may tUH H 
had qf the Puhlither, prict lOrf. 



C..,r, 



■'1, Rocki Un Rfvtew. Tnv- 
I < ■ \j.i Uio Prtnler; ot u» IL- 



aQ 



PrUit*dby OFkavvii. 6. W)i 

I*tit>h>licc| cv«r/ Salurduy ' 
Hciw, «nil niiy br bad ul nl 
Town mdJ Ctfuuiry. 



Vila Eud 

. II. 
>ud ^« 



W WIW to 




THE 



AZINE OF SCIENCE, 



^nO ^Ijool of ^xi^. 



OIL] 



SATURDAY. JUNE 13, 1840. 



[Prtck 14^. 




t^Atrimm m9ffriUHt. — 2. Pd/cM/A^r^M minH*.— 3, Anojtiafherium nimmunr, — I. lehihyntmnrita 
ytutifodtm. — 5, Pftmosttunu doiicA^i€ini4,-~-C. Pier9tiacijflH$, 



ORGANIC REMAINS. 



rcmirWji iu b» GtvAogy, tlmt a close 
I of recent anJ foMiI species of aniinttlii, 
breace* tlrawn in regard to their lubitn. 
tlic geologiit to coutemplute the earth, 
eeo a( suocesaive periods the dwelling 
imals and pUnta of ditfrrcoC raoea, aoDW 

othen aquatic ; some fitted to live in 
to ia Ike water* of lakes and riveri. By 

ion of theati topic*, the mind ia slowly 
blf withdrawn from Inuginory pictures of 
v and cbaotic confnalon, such as hjinntcd 
Itioa of the early cosmogonisCs. N'ume- 
are discovered of the tranquil depost- 
ImcntAry matter, and the alow develop- 

ic lift. The growing importuce then 

• II. 



of the natural history of organic remalrut may he 
pointed out aa the chAract«ri»(ic feature of the pro- 
gress of die sdencc during the pre«ent oeatuiy. 
This brancli of knowlcdgr has already beoone Ul 
instrument of great utility in geological dosaifioa* 
tioD, and is cootinuing d^ly to unfold new data fbr 
grand and enlarged vicwa respecting the former 
changes of the earth. 

In taking a brief review of the progreat of vital 
Bxistanee, from the etriiest period of the earth't 
history to the last great changes, U is reqnirite to 
refer to the position of the varioas rocks and de- 
|iosits upon each other, as explained in No. 5&» 
page 18. The primary, or unatratiHed rocks, u 
there explained, consist of such u formed the firtt 



MAGAZINE OF SCIENCE. 



I 



emit fl&d which cAosHtntev the lowest bed npon 
which bU the rest arc placed. The«e primary rocks 
contain no rvmains of ontauic matter which ever 
had life, or it should rather be said that we have 
jet diKcorered none, cither aniroil nor plant. 

The ran^ of rocks which come immHiatelj over 
these 14 called the Oraawacke group, and consists 
of states, transition limeHtonp-S, Ace, and abound 
with fotsU remaiuM, of sach a nature as to show a 
very groat rariety of structure, habit, appeaniiice, 
and locality. No mammalia nor reptiles are yet 
discoverable, but the vahoos slate and limestone 
beds contain many species, which, althdugh bearing 
but an cxtreniely minute proportion to the vayt 
moss of the earth, are yet the nndcus from which 
to date our re»earches. The plants of this group 
are about Iwclve in number, and consist of gigantic 
Perns and Gqui!>etum8, nor it is nippoted capable 
of sustaining animal life, though what other more 
fragile plants might liavc existed we have no records 
remaining of. Of zoophites or corals there have been 
discovered at>oat 100 B|>ecies; of Mollusca, Ra. 
diata, and Cnistaoea 460 species ; of Fiab 2 species. 

The Carboniferous group, or Coalroeasnres, yield 
animala of similar organization, and in greater 
abundance ; this period also produces various 
coniferous trees, which did not before exist. The 
whole nam>>er of genera and vpecies varies but 
little witli those discoverable in the former group, 
and very luinierotts genera run through both. 

The red sandstone group valuable as it is to the 
builder and the miner, is yet not more prolific in 
fossil remainn than the former deposits, yet hcxe we 
first And rcptilet, showing another approach 
towardi the present races of animals. In the va- 
riegated marls, no If.is than four gigantic rrptites 
have hern fHsooverrd, the Phytosaurus, Mastodon- 
sauruii, li'htbyoaaums, and Ptesiosanrus. In other 
of the Bandatone group, the same or saBular Sou- 
rimu, or n*p tiles are Cound. 

Tlie Oolitic group which contatas among other 
roek*. the lias, ytclds very numerous ■prcin. The 
remains of plsiiti* are. howcvrr. so little varied that 
we are not cTmblrd to form a Judgrmcnt of th« 
gwanl v«|«tation of this period uf crration, but 
animal axiatenoe offera itself to uur notirr with 
«OBtinned |»Togreas of development. S)m-II« are 
common b<>th univalve and btvaUe, ro Are »\*o the 
loophytpf and other animaU uf timpir or^qniiaLiun. 
Reptile* too are by no means rare, either in this 
covntry or on iJkc continent. Insects ftrat make 
their appcamticc. Fiobmraof very freriurnt n^ur- 
nnce. a bit J and two tpedm of mamnmlia (the 
I>ladel|>liis)havelirciifewid. Of the various reptile* 
of this |ieHod, the Ichthyosaurus, particularly 
tba l.pUlyodon, seems to have been be»t adapted to 
nUa in the waters ; its powcrAil and caparioui jaws, 
■omdlBaa eight feet in Uugth. beinfi on overmatch 
Ibr Cbn eroeodUea aod pletioMuri of this period. 
Stnnfn InhaMtanta tbaae, Ibr as Cnvier aay«, ** the 
lehtJkyoMima has the tootit of the dolphin, the 
iMlk af a crooodile, tha hand uwl sUmnm of a 
Hlnnl, th» otrvoiitias at eataeea, (being now rreo 
four in number.) and the t w fb f of f|«h : wMle 
tha Plrtloaaaras has. with tba same oetaoeo«a n. 
tnoittea, the hesd of a linrd. and s ne«tk 
llM bodrof laerpcnt." It b aJmnat 
to Hf that thaaa two gtnera have diaappmroJ Ann 
llHOTrihea of our planet. We mnst not ftiifil son 
' riy to allude to the flrvt Inrd. Th« PImo. 
of »Uch is nwwaCrd in the eot 



hatai osvght by the 



UpeM tho 



TaiOr. 



Oolite repoM flie Wealden rocks, in IW hoi tf 
which has been discovered that eaormoi 
the Iguanodon together with Croeo«IRf»a, 
and other reptiles. While npon thia Is 
chslk, in which deposit the larger n'litiiis 
were so frequent st a former period, are ■• 
discoverable. The remaini of the erocxidllc. i 
or two other reptiles, ar^all that hate y«< he 
up. 

Above the chalk we first discover f w wioo C M 
of mnmmifrmus animals. In the Oy|a^BL 
Palevtherium moguum, minus aod 
species. Anaplotherium commnne aM 
remains of lome canine anlnial. mtm 
hare resembled a squirrel, and many 
species of fthclU. 

The marie, claya, and gravel abww 
yield a still greater number of fWUf 
creatures and vegetables. The ImpO f 
higher order of vegetation, and the 
covery of the foseil remains, and ev 
bones of the Mastodon, HippopotamitB, 
Horse. Ox, Hysna, Biear, Pox and h 
not only the recent formation of thia 
rocks, if such they can be called, bvl kria% 
to a period but little anteoedrat to Ihi 
preeeot creation — when the worid wan i 
cr ea t ur ea similar, or nearly similar lo ^km 
now roam over ita niHkoe. 



PAINTING IN CRAV0K8. 

Bt crayons we underxtand in genetnl «n 
stouea« earths, or minerals, and aobaUncosi 
drawing and painting inpatlH, wbrtkar 
stances are asrd ir. ihetr nnginat 
only cut ttitu long nnrrciw sJipa lor 
lo a paste with gum water, «c. 

Of iMe ^fat4rrulU lued in T^ ci,<» rn'mtkj TU 
perfection of tlte crayons a prai mt^ 

sure in their perfect sofU.' .aip4j«stbl«la 

execute a brilliant pictiiit: «tLh iLcui if ihey lA 
otherwise. 1 he best pastils or etmyouft art* ihM* 
imported from Switzerland, but b«i>s nan as- 
pensive than those made here. tWy wo tarn 
m an uCftc lured nearly as fine in ' ' 
principal, with their different ohadi 
li>w* :^whae, black, yellow, orasre. 
blue, green and brown. Itrm 
which is of a whited broan t 
better.— strong blue paper, wl... „ ,, . 
noeaihlc to get entirety free tnm kBOto( 
knuis roust be levelled with a Mn-ladliB, flC: 
otherwise Ihey will prove irouUaoomeu Caa 
IS a very good sort, as U diattitmtei th« 
tlie heat advantaro. I'he paper muiA 
very smooth on a linen cluih, previonol 

on a frxnie uliii h it<.iv ).■• ,\r%,,m }fj djOl 
fn >jtttii tMCki 



tl. 



I). 



yr.tit x-i 



»'' I >acv a piece oi wmi 

^I ' the ainlalns fimao 

P^l ipoBH, koopfsiff it 

one hand, nib thecloth gvnily tu lh« m 
other, tlim turning the ttim9 wiu a 
while pa)Ntr in your hand, ntt dooe th«^ 
whan the paiio la perfectly dn 7011 way 
with the paioUiif. The artiatk ot4e« tn ki 
ooton ioponuo ohmld be vtnnr4 with 



4(ridodl8toftM»b«rofioiUbea». Iho 



MAGAZINE OF SCIENCE. 



83 



deposited acconJing to the itereral gn- 
lights. The box iiiadc line of should be 
«illi nine partilions. In Oie 
left IuihI. (sup]H>fltiig UtL* box 
he paints, which is the best 
1^1 lum ptncc the black and ^y crayons; 
>Dd partition, the blues; in the third the 
id bn>wn9 ; in the fintt partition on the 
of the smrond row, the CArminps, lalce«, 
%»t and all deep reds ; the yt>llows and 
the middle, and the pearly linti next in 
(t TOW i let the (Irsl parlition cuiitaiii n 
fine llncu rag, to wipe the crayon^ with 
~ng Ihem; the second, all the ptire lake 
iltion tints; and the other pnrtiilons may 
thuae linta which from thrir miiiplrx 

not be clasacd with any of the forotcr. 
kmt /or using Ue Cratfomi. — When fhe 
inta immediately from the life, it will 
prudent to make a correct drawing of the 
another paper the size of the picture 
to paint, whirh he may trace by piercing 
iog with pin holes pretty close tocccther. 
' intended to be used for the paiDtinc 
id upon a table, and some Bne pounded 
lied up in a pieco uf lawn ; rub over the 
d atrokes which will gire an exact out- 
dent will find that the itUing posture, 
hiiX of crayrtiis on bis lap. the iiio«t ion- 
Qthud for liim to paint ; thut pnrl uf the 
1 which he is at work should be snme- 
er than his face, otherwise the arm will 
d. The windows ought to be darkened 
t feet from the gruund, uud the subject 
ited should be situated in such a manner 
light 8h>uM fall with every advantage ou 
ftToiditjg too much stmduw, whirh M^tdum 
d cffict in noitrait puinline, cs]ie».i^lly if 
be paints has any degree of delicacy. 
Mcs of the face bclup; carefully drawn 
[k. Uke a rrayon of pure carmine, and 
draw the noslnl and edge of the nose; 
ahadow ; then with the faintest carmine 
ia the itrongest light npon the nose and 
which must bo executed broad, then 
gndual)]i with the second tint ind the 
Ig ones, till ho arrives at the shadnws, 
be covered, brilliantly enriched with 
inc. a little broken with brilliant grAen. 
lethod will at first nffeusively strike the 
its crude appearancii, but in tinir^liing it 
good foundation to produce a pleasing 
lors bring much more easily sullied when 
, than when the first coloring is dull ; the 
larly tints diacemable in 6ne complexions 
Itde with blue rerditcr and white. When 
i the eyes, draw them with a crayon in- 
the carmine tint Whatever color the 
of, lay them in brilliant, and nt first not 
ith color, but ejceciited lightly ; no notice 
of the pupil yet ; let the light of the 
much to a blue cast, cautiously 
r starring appearance, (which when 
doccd is seldom overcome, ) prescrriug 
ihadow thrown on its upper part by the 

snd heavy lint is alswto be avoided in 
irows, it is therefore best to exocuto them 
Md glowing shadow at first ; on which in 
^ng, the bain of the brow are to be 
by which mrthod the former tints will 
insclvcs thnnigh. and produce a pleasing 
rgtn the lips with pure cannine and lake. 



and in the shadow use some carmine and black ; 
the strung vermillion tints shi<uld be kid on Hfler- 
ward^, from the corner of U»e mouth withf-armine, 
brown and greens variously inlormixod. If the 
hair is dark you should preserve much of the lake 
and deep carmine tinta thereon ; after you have 
covered over, or dead eolored the head, you nrnsi 
sweeten the whole together with the finger, or a 
slump. Beginning at the strongest light upon iltc 
foreJiead, be cauttous not to smooth or sweeten it 
too ul\en. as it will give it a thin and scanty effect ; 
if yuu hnd it necessary you must replenish the 
piciuro with more color. When the bcail is lolo- 
mbly adorned, the back ground is to be begun, but 
iu a different way ; it is laid in very inui and 
rubht-d into the piiper with a stump. Near the 
face the paper should be almost free from color, as 
by its thinness it will give both a soft and solid 
appearance; tlie above method being properly 
executed will give the appearance uf a painting 
principally composed uf three colors, vis., carmiae, 
bliick and white, which is the best preparation for 
producing a fine crayon pictiue. « 

The next step is to complete the back ground 
and the hair, as the dust in painting tliese will fall 
on the fscc and injure it; fro.n Ihonce proceed to 
the forehead ilaishiug downwards. In painting 
over the forehead the last time, begin the highest 
light with the most faint vennilUou tint. In tlie 
next shade succeeding the lightest, you must work 
some light blue tints, composed of vorditer and 
white, and sweetening them together with great 
caution ; some brilliant yellows may also bu uved, 
but sp&ringly, and towards the routs uf the hair 
strong veruiter tints mixed with greens will be of 
service. Cooling crayons composed of biack and 
white should succeed Ihese, and mull into the hnir 
beneath the cyeft. tile pleasing pearly tiiili arc to 
be presen'L-d. In finishing the cneeks let the pure 
Like clear them from any dust ; then with the lake 
may be intermixed I he bright vermilHon. The 
eye is the most diificult feature to execute in 
crayons. When you want a point to touch a small 
part with, break off a little of your rrayon against 
the box which will produce a comer lit to work 
with in the minutest parts. 

The difiicuUy with respect to (he nose is (o pro- 
serve the lines distinct, and at the same time so 
artfully blended into the check as to express its 
prnjoction and yet no real lino be perceptible. 
The shadow of the nose is generally the darkest 
in the face, carmine and brown ochre, carmine 
and black will compose it best. In fmishing tho 
tips, use strong vermiUions, but wiiJi great c-aution. 
In coloiing the neck, preserre the stem of a pearly 
hue, and the light not ao strong as on the chest ; if 
any part of tlie breast appears, its transparency 
must also be expressed bv pearly tints, but the 
upper part of the chest should bo colored with 
beautiful vermillions deli(»tely blended with Ibe 
other. 

CHALK DKaWINO. 

Charcoal is used fur slightly sketching in the 
outlines of figures, iu order to get the proportious 
previouK to making a drawing in chalk. 'Ihe best 
charcoal for this purpose is that of the willow; it 
is cut into slips, and the strokes made with it may 
bo easily rubbed otit. 

Black chalk is a fossil substance resembling 
slaty coal, which is cut into slips for drawing, it 
is gencrailv used iu a port crayon ; it is much 
employed for drawing figures, and is the bc«t mth- 



* 



MAGAZINE OF SCIENCE. 



slAncG t'orUiis jiurposc, in making drnwinga from 
plaster fig^ircR. r>rfnifii liTe. Il is more gritty thsu 
black lead, but is of a de(f]>or hlitck, Oiid haa not 
the f^losainesji of ilu* furmcr ; it uiny be procured 
hard or »ofi — ihc beat is of two kinda* the Krcnrh 
Aii'i Italian. White chnlk ia ui»pd together with 
black, for laying on the light for meliowiug and 
Rofl«imt[E the ahadowb into each other. Stumpa 
are usod — llicy arc pieces of »oft leather or blue 
paper, rolled up quite ti^ht and cut to a pomt. 
Middle tint paper is of a brownish, or grey color, 
which is tiscd for drawing upon with block and 
white clialk. 

In drawing after a plaster figare the eye will 
eajiily dificover the general light and shade ; the 
mau of light should be kept broad and be well 
attended to before the smaller parts are divided. 
The outline should be excvedingly faint in such 

Enrts lis receive the light. The abadowa may be 
lid on by dra^int; parallel curved lines according 
to the aituution of the part, crossing them occa- 
siuncilly, and softenin;; them in with more delicate 
lines when necdpsary. All the parts of a human 
figure are compowd of curved Aurfacos, no straight 
lines ar« ever admissiblo ; every line should have 
a graceful turn. Care should be taken that no 
lines ever cross each otlier at right angles, neither 
should the crossings be (oo oblique, tis Uien they 
are confused ; a proper medium will be acquired 
by the study of good drawings, or prints. Rubbing 
the shadows in with a stump is a very expeditious 
way, and produces a Rnc ellect ; but it tdiould be 
used with ditiCTOtion, as it is better to exocute (he 
shadntvd in ft clear and regular manner by soft 
linos. 



ON THE FLAME OF A CANDLE. 

On examiniug the flame of a common candle, we 
find I hat it consists of three different portions; llic 
'lowctil pnrt which is blue, liie dark centre, and tlte 
main body of the light which is the brightesL 
The cause of ihcse differences we shall proceed to 
explain, premising however, that the flame of the 
candle is caused by the ignition of tlic carbon into 
which the wax or tallow is converted by the red- 
hot wick. 

This carbon at the lowest part of the flame, 
immediately meets wilh a current of fresh air, and 
is effectually burned, none escaping id an ignit«d 
state, which is the case higher np. That this is 
the true reason, may be proved by supplying plenty 
of air to the upper part by meaus of a blowpipe, 
when thill portion will become blue on account of 
the sudden and completo combustion of its carbon 
by the full supply of^air. 

Higher up however, through the greater quantity 
of carbon evolved, and the rarefaction of the 
ntroosphcro in its immediulo neighbourhood, by 
the heat, the supply of air is Icaa; and, conse- 
quently, the carbou is dilfused and floats in an 
ignited stfltc during combustion, and is not com- 
pletely buruod, for a portiou remains uucousumed 
in Uie shape of smoke orsool, as is seen by holding 
a piece of wire in the upper part of uie flame 
when it will soon be covered wiili aoot, which is 
not the case when it is held in the blue portion, 
where all the carbon is imnicdialcly aud completely 
consumed ; and as the aii is most rarefied ana 
healed at the lop, (which is ihe cause of tlie 
pointed shape of thu llamc.) therefore, at that part 
the carbon receives least air, aud consequently 
must amuke is evolved. 



But in ihe inierior of ihe flimo Uut «rT 
receive no air, whence it it unconwiro*' ' 
there and forms the dark central part. 1 
burnt vapour of carbon, may be trd & .. 
meaus of a short tube, at the end. uf whi' 
be ignitud. thus fonuing a second namv, wbtvii 
if large enough might be treated in Uie nana vayi 
lllu^ prc'ducing a third ; and aatislaetonly deoiMl* 
SM-niiiiL' thai the dark portion consists oC At 
unbunii raibon- 

Thoso then are the reasons of lite varior ^ 
in the flame; at the lowest pArt the c . 
GonipleLcly and suddenly burued. produ' > 
blue Home; in the interior il u> asir<- 
forming a dark centre, and on the outside h\ ^.^^^ 
in a state of iinutioii dunnif combustion, the enpyly 
of air noi being suAicicnt to produce coiaplflli 
combustion. 

From our knowledge of the ooualructim, if 1 
may ao term it, of the flame, we derive acvenl 

S radical advanlAges; for we see ihai by 
ucing a supply of air into th«' i entre of ihc 
it would be consumed aud the light in< 
(Jn this principle the Argitud burner is formet), 
where the air rushes up the interior of the ' 
wick ; thus Uic carbou gets more air aud 
is increased. Vet the curbou is now cuiir>-o 
consumed and soot is formed, so that if we coald 
draw more air to its 8upp<jrt by any means, the 
smoke would cease and tJie light would bs 
brighter. This we effect by tltv lamp glass, whiob 
acts as a chimney, creating a swift a!>ceul of froidl 
air, and yet by its tronspHrcncy offering no iio« 
pediment to the light. 

But if the wick be turned up too higli* more 
carbon is ovnivud than can be cousumcd, and il 
therefore smokes, which is al»o the case wh 
nir holes are stopped by dirt, burnt wirk. ■ 

And in conclusion, by gr»alW aui: 
supply of air by the blow-pipe, iho 
tensity of ihe name is so much incii'<*»- <• n m "- 
are enabled lo fuse gloiw, aud even metals. 



COFFEE, 

Tbv coffeo shrub is a plant of Ihe samr nrmHT as 
madder, namely the nibiaceir of Ju • 

arranged by Linn<l m his class pti >»i 

order monogynia. There are aevcral »pccu:« of 
coffee ; but the only one cultivated for use, is Um 
Coffea Arabica of modern botanists. It is a natttt 
of the rpper Ethiopia, and grows about 14 orSU 
feet high : the branches conic out m pairs, oppoiiUr 
each other, and crussiiig the pair vf branches thai 
come out below aud above them ; the leaves an 
somewhat like ibose of the bay, but les^ dr\', and 
thinner; the flowers arc while, and pncctcded by 
a berry like a cherry, filled with a yellowish pulpi 
and two small hom-like beans, flat and gr^itd 
on one side, aud convex on thu other. 

It was a few years before 15tA^) thai the iufusioa 
of these berries came into use as a dxiuk, and il 
has slowly extended itself through most parts uf 
the civtlizeil world { except China, and Moroccii, 
in which the use of lea ia mure commou ihaa 
that of coflec drink. 

tt was probablv the clastic homy nntnrr nf 
these beans, whicL renders them very i' 
either to powder or for tlic water to penclni: 
originally led the U8«n of coffee drink lo loiut 
the beans to a brown color, in order that th^y 
might grind thorn more easily, aud exUacI the 



MAGAZINE OF SCIENCE. 



85 



nore speedUf. The roasting not only 

vwtn UMC purposes, but aliio dcvd- 

or odorouB principle oi the cofTee 

to rout cofTee properly, the iue« of 
DDl bo lott sight of^ namely, lo de- 
ni'like t^nftcily of the icrven bean, and 
il« fine Accnt. Too miu-h heal would 
chemitfll eletneiils which ought lo be 
And wDutd substituto in their plaeu 
h are entirely dificruut in quality. TUhI 
which pleasofl e*o grenlly the admirer of 
, is succftided, when the collV-c i» ovcr- 
<j a biiier taste and burnt smell, which 
pleoitiiut, and even disagreeable. It, 
er h^tiiil, the ronsting process irt under- 
thr herti to wliirh the beam have been 
has not been suiHcicnt, then the raw 

• ool^<^e reniainft, and of course diini- 
aroma, which requires a certain heat to 

There it of rourse a jnst medium to 

Well roasted coffee ought lo hare 

l&te culor equally spread over it, which 

D to those who arc in the habit of pur- 

opcralion; but it is never necessary 

rofulcd beans, the scent is sufficient; 

• true aroma, is developed, and Hll^ (he 
atmosphere with ita delicious scent, 

time to stop the roa'^tin^. AAcr llus 

oil acquires a burnt flavour, n scent 

resembling that exhaled by smokers of 

perceivi'd, and instuiid of g»ud roasted 

e is obtained a bad kind of charcoal. 

inj; the importance of this operation, it 

cr lliat some of those who are very fond 

uk, nlthongh ihcy would feel ashamed 

themselves in any other department of 

economy, yet do not hesitate to roast 

, not only at home, hut even with 

The fragrancy diffused by the 

to delight them ; and they appear 

by anticipation, titc plcasare they ahali 

ft drinkmg of Ihc infusion. 

iw coffee loses from Iti to 2U per cent, of 

h by roastmg ; if it loses more it is ccr- 

■snnstcd. Many different modes are 

EMhch has its admirers; but there is in 

paingle rule to be observed, namely, to 

|»per degree of heat, and keep it no at the 

1^ until Uia roasting La ffoished. W heiher 

Ig is performcit in close or open vessela; 

Iw coffee is leA to cool in the roaster, ur 

Nit» or even laid between cloths, appears 

I If, indeed, tlie roasting is corned by 

DO far, the coffee should be immediately 

Ihia on the floor, to cool it as soou as 

In all cases, when cold, the roasted 

id be put into lin-plala boxes, and kept 

niaturc. 

ts have made cumparalive analysis 
roasted coffee, of which some account 
r be given ; but at present there is 
for detaihng the best modes of making 

w<dl known that the chemical action 
lis bafttened, in general, by reducing the 
>wder ; it is necessary to grind the 
Fee more or leas fine, as it is intended to 
less or more heated. To reduce 
fine a powder, although it would rc- 
lUghtly wann water ^>o extract its 
is, yet It would he inconvenient in oilier 
>r the powder wtivild pass through the 
IJitA coffoo pot, and by also remaining 



suspended in the water, would render the clearing 
of the drink ditBcult. At all events, roasted coffefl 
should never be ground but the moment before it 
is tued, as otherwise U loses much of its fiue 
ttcent. 

It now remains only to say a few words respect- 
ing the making of the ground roasted coffee into 
drink, — and here the grand points otl-, not to lose 
the Hue aroma, and not to extract the bitter, acrid, 
resiiiuufl clement of the coffee. To avoid both 
these iucunveiiiciii-es, it LB necessary that the coffee 
drink should not be made with loo much heat ; as 
this would dissipate the aroma in vapours, and 
cause the water to dissolve the resin. The coffee, 
therefore, must not be boiled in the water, and 
still less is it proper to boil the grounds over Agaia 
with fresh water, as is done by some persons. 
Coffee diink made fruin the gruunda, when it is 
added to that made from fresh ground coffee, gives 
it indeed a fine deep culor.'but the taste of the 
drink is very bad. 

It is not even necessary to pour boiling or eveu 
warm water upon the ground coffee, cold water, 
if sufficient time is nllowed, makes equally good 
coffee drink, for tho elements to be extracted trom 
the roasted coffee are extremely solnble in water. 
Bat if the coffee is required to be prepared in 
haste, hot water must be used. 

It is universally agreed on by the French ama- 
teurs of coffee, that coffee drink is never so good 
as when, aHer being made with cold water, or with 
hot water and cooled, it is heated over sgnin, 
carefully avoiding a boiling heat. This healing 
over again is nupponed lo cause the various elements 
which produce tho fine flavour of this drink, to 
unite more intimately; anr this may be the real 
fact. The excellency of the cufiec sold at Paris 
is well known; and this is alwayi made one day 
and healed oversgAia the next day, wheu wsnted. 
A further advantage aticnds this knowledge, of 
cunitequence to single persons who. in summer 
time, do nut keep a Are in their chambers, tliat by 
merely pouring cold water on the ground coffee 
over night, and stmiDing it in the morning, the 
strained liquor may, while they are tlressiug, be 
healed sulllcienlly for drinking, over a lamp ; and 
this gives coffee n superiority over tea for the 
breakfaifi of such persons ; as tea requires the 
water to be boiling hot, in order to extract Its 
virtues ; and of course requires a fire lo be 
lighted. 



PREPARATION OF CATGUT. 
(lUtumtd from pag9 &6, and concludtd.) 

Catgut for Chek-makera. — ^Thts kind must be 
very tine ; and of course requires the smallest in- 
teitioes, well prepared with potash. Sometimes 
they ore made by cutting, with a particular kind of 
knife, the intestine into two strips. Tbe knife, 
wbicbis fixed on a table, has two edges, in opposite 
directions ; and above tbem. a ball of lead, which 
is introduced into one end of the intestine ; and by 
drawing the latter continually over the ball, the 
projecting blades cut it into two strips, which the 
workman holds, one in each hand ; drawing them 
regularly, till it be cut quite through. 

^^'atch and clock-makers also uie catgat of 
various sizes, consisting of more thsn one intaitine. 
and made like tbe musieal instrument cords ; which 
we shall next describe. 



H 



MAGAZINE OF SCIENCE. 



Caiffut /br Muaicai hutmmentt. — Of nil the 
corda (roiB iotestinea, tbiB kind is tfae moat difficuit 
to tDAke, and reqnireA the greatest care and ability 
of the workmaa. It is ackDOwlrd^ed that for maay 
yean thej bare been made aa well in EogUud a< in 
lUlr, with the exccptioD of the trcble-itiings for 
viobaa, which our manufacturers hare not been 
able to imitate, but on a very limited scali-. Thtt 
ifl either owing to the diffemice in quality of the 
intcatioes, or some other unknown caaie. Whatevirr 
it be, we are KtiU tributary to Naples for this 
article ; and every exertion ought to be made to 
free «u from this neceiaity. Kxperimenta, made 
with skill, will DO doubt luccecd ; and tbe Society 
for the Encouragement of Arts, by calling the 
attention of artista to this subject, will have the 
glory of contribottng to the perfection of an art, 
Bf which little is at preaent known. 

The cleaning and Mraping of the iateiUnea for 
this purpose, to free them from the fat, mufit be 
done with much more care tlian is rcqutsttc for 
other cords ; ao4 when they have undergone that 
proocM, they must be steeped in an alkaline lye, 
prqwred as follows : — 

An earthen pan, holding six quarts, is filled with 
water, and three pounds of potash are added to it ; 
which must be well stirred, and lufTered to sab- 
nde. lo a similar vessel, full of water, placed by 
tbe side of it, are put fire pounds of pearl-ash ; 
learing that also to settle. If it be wished to make 
use of this solution within a short time, it will be 
necessary to add to it a little alum-water, which 
will clarify it quickly. 

The scraped tntestinM are now put into earthen 
pans, BO as about to buf-fiU them. The pans are 
then filled up with the solution of potash, with as 
much water added as to double the quantity of 
floid. This liquid is changed twice a day, in- 
creasing itj strength each time, by adding more of 
the solution of jiearl-ash, and dimioi&hing pro- 
gressively tbe quantity of water ; so that the last 
solutions be the strongest. The intestines gradually 
become whiter, and begin to vwcll. After having 
Buffered them to macerate from three to five days, 
or more, according to the state of the atmosphere^ 
the operation proc«eds as follows : — 

Every time that the alkaline solution i» changedf 
the pans are placed upon the box called the re* 
frttherut placed on a table, or oo tresuels, 19 a ^ 
slanting direction, so as to facilitate the running ofT 
of the water. This buz must be large enough to 
hold the frame on which the cords are to be stretched. 
The intesUoes orv scraped with the edge of a copper 
cube held in tlic lef^ haiid. 7*lie furtrfingcr of the 
left band is placed near to the edge of the copper 
cube ; whilst, with the right hand, each intestine is 
drawn o^er the edge of the disk or cube, and 
between the forefinger. 

When they have all been treated in this manner, 
and placed in a fresh pan, a ptronRcr alkaline 
solution is poured on to them than that from which 
they were last taken, as we hare before mentioned. 
This operation is necessary for cleansing tbe in* 
testineof its greasy quality, and bringing the cords 
to perfection. 

As soon as it is perceived that tbe intestines 
begin to swell, and some little bubbles appear on 
their surface (for in tJiis state they rise in the 
water.) it is necevsary to twist them iinmedi/t/fly, 
or (hey will besin to shrivel ; which somntimea 
happens, particularly in summer, and occasions the 



loss of the intettinra. and also the time spent ofV 
them. Ib hot weather, the iotc&tioes are, indesiti 
mo«t easily cleaned from fat ; but Chen tbe workma 
must be more than ordioarily attentive; and tfae 
different lyes for the washings must be owlr 
stronger with alkali, and applied more quickly, fat 
winter, all goes on in better order, and the oper«tioB 
is more certain. Tlie manufactuneis of Ihia 
gfflwrally place their workshops in cool 
where there is a little dampness. 

The intestines being now ready to be twisted, 
ore taken out of the alkaline aolntion. 
manufacturers plunge them again into fresh 
and wash them well thcredn ; but, although 
become, by this method, of a belter oolor, 
take the solphnr better, they run the riak uf beti^ 
weakened. 

To twist and finish the cords a mackioe is 
a kind of frame, two feet high, and fire feet 
00 one end of which are placed a number of pegs 
and in the opposite end are bored, with a larp 
auger, a number of holes, inclined in such a w^, 
that nheo pegs are placed in them, to attach tfei 
cords to. they may not be lisble to slip and 
out. Tbe intestines are now selected occordh^ 
their sise ; and two or three of them are takeiit 
the ends twisted round one of tbe pegs first 
and tbe other ends are carried to the oppostle 
and attached to them. Tao turns of the iotee! 
around the pegs are sufficient to prevent 
slipping. When fixed to tbe pegs, they mast 
l>e drawn tight ; as they wonld be anbject to WO* 
during the twisting, if eufTicieat play were not giveii 
to them for that operatioo- 

If any of the intestines should be foond Co9 
short to reach the opposite side of the frame, tbef 
must be lengthened, by pieces cut off any othtn 
which may be too long ; and care must be taken to 
make the ligature near the last-placed peg, to pre>j 
serve the cord of an equal size in its whole l 
as otherwise it would be false in its tone. 

Tbe frame being filled up in the manner we 
described, two or three of the pegs, bearing 
end of tbe intestines, are Axed to the ipindl 
the machine contains several, and turned 
several times ; passing the finger and thumb of 
left hand frequently from one end of the cord tv 
the other, beginning at the spindle. When all th» 
cords have undergone this operation, and the 
are all replaced, the whole frame ia placed ift 
sulphuring closet, with several others ; as it 
not be worth while to sulphur one at a time. 

Tbe salpfaitriug closet is placed in a damp plant, 
surrounded aa mnch with water as poasible. An 
earthen vessel, oontatnlng tbe aalphar, is placed 
it, with the frames ; the sulphur is then set on 
and the closet well dosed In every part, to co 
the fumes. When the cords have remained a 
sufficient time — which, of conrse, varies \n soma 
measure, according to circumstsnees — the frames 
are taken out, and placed on the rc^»Aer, and 
nd>bed with a horse-hair cloth. This done, 
are again placed in the frame, twisted anew, 
returned to tbe sulphuring closet, to undergo 
same process as before. If the itate of the 
mospherc require it, the whole of these 
moat be twice or thrice repeated ; and tbif 
then h;ft to dry. 

When the co^ is sufficiently dry. it is h 
by its not running up when a peg is takea oat, 
remaining stiff and etraight, Instead of 



MAGAZINE OF SCIENCE. 



87 



U diy raoa^ch, they are veil oiled with good olire- 
eA, *iul tMiiiled up ioto riogs for sale. Tbey become 
btfBcr hj lieinp kept some cime. 

To make the fourth strio^a for Tlolins, or any 
other fijwd cords, intended to be covered with 
meUl-wirv, the prooeu ii to well known, that it 
n«d Tiot b© here detcribed. 

whole Riccets of these opcnitionB depends 
illy 00 the ability and eiperimce of the 
wot A. turn in managing tlic ditTerent waihinga, 
KrcCcbings and twUtings, and in a judicious ttH of 
iKe sulphur- \Vbon the cord is too much sal* 
pfaoredL it reidily taaps ; and. on the contrary, 
when it i* not enough to, it stretches too mocb, and 
M«cr keeps in tone. 

We may conclude, that there is no fixed rule yet 
•idopted for the success of this hrsnch of manufac- 
Care ; bat we have much expectation, that we eboU 
MOO be «bie to Attccced aa well as the Italiana. 



PATKNT GELATINE; 
aa rBKrARBD ot mr. hbuson. tuh patsnter. 

liuTT of our readers must have seen a beautiful 
aflicle exhibited for sale in some of the London 
shops called " Prepared Gc!aLine," and which is 
for the making oi Jellies and soups— 
[BUtritious, pure, and tasteless, until flavoured 
teeordiog to the purpose for which it is tnlended. 
Hm method of manufacturing this excelleut 
•itide, (for excellent it is), is deacKbed as fuilows 
by the Patentee . — 

" When the cuttings of skins, parchment, Ac, 
have been freed from hair, fleso, and fat, and 
waohed clean in cold water, I score the grain side 
el ihem to the depth of about an eighth part of 
aa inch, in Lines about an inch apart, in order to 
facilitate the action of the alkali which I use, and 
10 render such action more uniform. 1 tlien 
iftnl' them in a causiic solution of alkali 
•I ft (es|»erature of about 60 degrees Fahrenheit, 
mtn^ for this purpose brick vats, or vesselfi lined 
vifk cement in the ordinary manner, and tliosc 
fats or vcnets, which I call the macerating ves- 
aeb, mu«t be covered with lids excluding the 
IPBcral atmosphere ; any vessels which are not 
act«>d upon by the alkali, may bo used. I thus 
laacerate the cuttings until 1 can pass a fork or 
tay other similar instrument through them with 
litt&c recistance, and I generally find tliat they arc 
ioficientl^ macerated in about ten days, The 
•Ikili which 1 prefer for my solution is soda, and 
ire my solution in the ordina.ry method, using 
parts of the common suda nf commerce. 
two parts of fresh-burnt lime to sixteen 
water; or any quantity of fresh-burnt lime 
;ieDt to render the solution caustic may be 
Mi'hon the process of raaoerftiion is suf- 
Ltly complete, a« aUcndy pointed out, I 
the cuttings from the ablution, put them 
ui TcsseU similar to the uiacerHling vcascU, and 
which most also be covered with lime, excluding 
the general atmosphere, I leave them in such 
viMi ala thus covered until they have become 
•oAdeskUy soft. It will be ascertnincd whether 
<hn have become sulUctcntly soil by passing a 
kn or oilier similar ijistrument through them, 
ad when they have become sofficlenilv soft, the 
fcefc or other instrument will pass easily through 
ihoB. Whilst the cuttings ore titus left to become 
Nit, ihey must be kept at a temperature between 
M nd 70 degree! of Fab 



ihrcnhelt, and ts they 



become sufficiently solt as above pointed oat, I 
remove tJicm, and ! slice or split such of the 
cuttings as arc materially thicker than the others, 
in order to bring them to the same, or nearly the 
same thickness. I then put the cuttings into 
wooden cylinders, placed in water vessels filled 
vrith clean cold water, but care must be taken not 
to put into any cylinder more tlian half the 
quantity which it is capable of containing. Theso 
cylinders, which I call washing cylinders, must 
be constructed in isuch manner as to allow water 
to pass freely through them, and they may be 
fitted in the water vessels in any convenient 
manner to allow of their revolving within such 
Tesselfl. I secure the cutting? within these 
cylinders, and then I cause the cylinders to revolve 
slowly in the water, I have found cylinders of 
three feet in diameter a convenient site, and I 
cause thefe (o revolve at a roeed of about one 
revolution in a minute. Whilst the washing 
cylinders are thus revulving, I cause a current of 
water to be kept up throu^ each of the water 
vessels by means of an aperture at the bottom of 
the Teasel at one end, and a pipe at the top of the 
opposite end, through which pipe clean cold water 
Li cDittinually supplied. I continue the cylindars 
revolving in a current of water, as 1 hare 
dearribed, until the alkali is sufficiently washed 
out nf tlic cutliugB, and I generally find six or 
seven dayH sufficient for this washing, when 1 use 
cuttings of ordinary thickness; but whtn 1 use 
cuttings which arc thicker than these I continue 
the washing in proportion to the thickness of such 
cutiiiigs. When the cuttings have been thus 
washed I remove thum from the washing cylinders 
and place them in a wooden closet, constructed 
in the ordinary method to prevent the escap« of 
gnn, and there expose them to the direct acUon of 
sulphurous SL-id gas, produced by the combustion 
of sulphur within the closet. 1 continue the 
cuttiugfs thus exposed to the direct action of this 
ga.<i, until they have a alight exreas of acid, and I 
ascertain whether lliey have an excess of acid by 
tenting them with litmus paper in the ordinary 
manner. 1 theu remove them from the closet 
And press thorn by any ordinary means lo separate 
OS much water as possible ; and after they have 
been thus pressed, I put them into glased earth- 
enware vessels, or any other vefsels which are 
nut acted upon by acid. 1 call these vessels 
steam-baths, and 1 apply steam to them in the 
manner tuiually employed for heating steain-batha, 
but any otlier convenient means of heating them 
may be used ; I ihiu bring the cuttings to a tem- 
perature of about 150 degrees Fahrenheit, and 1 
keep them at this temperature; by means of a 
suitable wooden Instrument I stir or agitate them 
until they arc almoat entirely dissolved. The 
liquid thus formed is gelatine, and I separate it 
from the residiuum which remains undissolved by 
straining, and put it into vessels which I call 
.icttling vessels, and which are constractod in the 
same manner us the steam-batlis. 1 heat these 
settling vessels in the manner which I have already 
pointed out fur heating the atcam<baths. Whilst 
this liquid gelatine is in these settling vessels it 
should be kept at a temperature between lUU and 
120 decrees Fahrenheit, and I allow it to remain 
undisturbed in the settling vessels, for the purpose 
of clearing it, until 1 consider the impurities 
which It contains have sutlicieutly settled or sub- 
sided. 1 generally find nine hours sufficient for 
this purpose, but if the impurities have not 
sufficiently settled or subsided in that time, t 



MAGAZINE OF SCIENCE. 



I 



prefer to clciir it by jtraiiiuif; it Oiroiigh a wciollcn 
ulolh. I rcmovL' the liquid gelatine trum (he 
•eltling veucls by means of a syphon, but any 
other suitable meaiu may bv lued fur Uiis purpose, 
and aflcr it has been SDmclently cleared I pour it 
upon slabs which I call couIing-sUb« to the depth 
of about hftir ftti inch. These slabs may be of 
stone or marble, but they must have frames uf 
itome ronrenieut Tnaienul, at least half in inch in 
depth 6t(ed to their edges, and cnre should be 
taken to place the slabs in cool situations. I 
allow this gelatine tu remain upon the slabs until 
it becomes cold and sou into a firm subslanro, 
and I then cut it into pieces, and wash these in 
the w«.9hin|r cylinders and water vessels which 1 
have already described, in the same manner as I 
have already mentioned for that purpose in respect 
to the cutting, as I take them from the macerating 
vcsarls. I'his washing; must be continued until 
the csceas of acid is entirely or nearly allofrether 
removed from the pclaiine, and I generally find 
(hat three days are suiticient for this purpose ; but 
I ascertain whether the excess of acid has been 
removed by tt*Uin)r the gelatine with litmus paper 
in the ordinary manner. After the excess or acid 
has bren reuioved, 1 take the gelatine from the 
cyUndcrs and put it into the steam-baths, and 
ihcn diMHolve it by applying heat to the batlis in 
the manner which I have already pointed out for 
that purpose; but it will be desirable to avoid 
raising the icmporaturc of the gelatine above 85 
degrees of Fahrenheit. When the gelatine has 
been thus completely dissolved. I pour it again 
upon the cooling cdabs, as before, and 1 allow it 
Co remain untU it becomes again cold, and sets into 
a firm substance. 1 then cut it into pieces of any 
couvcnieut size, and dry it upon nets b^ ezposuro 
to a current of cool dry air, and when it has been 
thus completly dried, it is fit for use." 

The gelatine of the second quality is prepared, 
without the aid of any alkaline solution, by 
steeping cuttings in a weak solution of sulphuric 
acid, or subjectiug them to the direct action of 
sulphurous acid gas, nntil in either case they have 
imbibed "an excess of acid." Aficr tliis they 
are kept in wooden barrels for three weeks, at n 
temperature of about 70 degrees, and then put 
into a steam-bath and entirely dissolved. A liquid 
gelatine is then obtained, which is treated in the 
same manner as the liquid gelatine mentioned in 
the process before described, until it is completely 
dried and fll for use. 



MISCELLANIES. 

TrariM^ Paper, — Dissolve one ouiKt; of pow- 
dered clear wiilte rosin in two ouuct;> ofxpiriUi of 
turjieutiuc — then add 30 drupA of the CK^enie of 
lemons; shake it well for a lew minute.v With 
a clean painter's tool, varnish a sheet of ti:«.sue 
paper with tlie compound \ hang it up to dry for 
3U or 4tl minute's lltcn give the other sitU* a coat 
willi the name fluid, llie ti&sne pajicr mi prtjared 
is beautifully transparent, and it will kei-p its 
apjiearaucv for years. 

To make Spruce Bter. — Vai four gallons of 
boiling water into a tub or cask with four guUous 
of cold wau'r, by which you wiil get tlie pnii>er 
degree of hcatj then add eight pounds of treacle, 
and two or three tabic spoonsful of the essence of 
spruce: stir these thomughly well togellier, and 
odd a quarter of a pint of good ycasL It is now 




to t>e kept in a temin'rate tiliiation tJII the firr- 
meiiliilion is somewjiat abated, (wbieh wilt be in 
about 48 h(Mir.^,) and thco bottled nffj wlien iu (W4| 
days it will be fit fur use. 

Color prodmreil in Plate Glas§ bv the Suml't 
JTnys.— " It is WL'll known," Mr. Faraday remarks. 
"that certain pieces of plate gla*« acquire by 
dcgrt'i^ A jiurple lingt:, and aliimatcly become nf 
a cnmiwraliTely dtcp i-olnr. Tbf rhangc i^ known 
to be gmdual, but yet so rajiid, as easily to be 
nh9er%-ed in the ci>ur!«e of two or three years. 
Much of the plate gla<4 which was put a few 
years back into some of the houses in Bridg* 
i^treet, Blackfriars, thoni{1i at first colorless, has 
now acquired n violet or purple color. Wialiiu^ 
to ascertain whether the sun's ruvs had any in- 
fluence in protluclug thiH change, ibe following 
experiment was made. Three pieces of plate 
glass were soleclod, which were judged capable of 
exhibiting thiii change; one of them was of a 
slight violet tint, the other two purple or pinkisti, 
but the tint scarcely iwrceptible except by lonkinic 
at the edges. They were each broken in lwi» 
pieces; three of the piece!) wert; then wrapjied up 
in paper, and set aside in a dark place, and the 
correNjnndinK pieces were eitposcd to air and 
xnnshine. Thi^ was done in January, and in the 
middle of September they were examined. Tlie 
pieces that were put away from light seemed to 
have undergone no change ; those that were ex- 
posed totlie sunbeam!) had lucrrascd in color coo- 
siderably i thotwopAlertbemiMt, and that tusuch a 
degree, ihnt it hardly would have been supjaised 
tliey bad once formed part of the same pieces <if 
glass as those vrhich hud been set aside. Thus it 
appears that liin suu's rays cau exert cbemieal 
powers even on such a compact body and ]ief- 
manent a compound as glass." 



QUERIES. 

aOl^Wby doei a piece uf bnnil nrolnUU* Urn cfievla gf 

puniest moitunl .* 
20-1— wii; u It UiBi ll(ht puitBti UiToagha gntn wovUso 

blind tit\t9»n plttk f 
203 — \Vb)- <lv lli|iUdf Apptlctl to W9<id. ctuj* U io u|v«ft< 

(lurkcr thun ticf ore ' 

301 — Wbat wiLl (t*«trt>y tlio peculiw tm^il of aaplitha ' 

tO&^Htiw U braail la br invtlt' wdluiul yatwt * 

Bf^— Wbat U Iks eauve of some diiUlloa spintii iffOtwUi^ 

a oUlky appearMK* wb»a diluted wltt) wilsr J And i>y what 

ra«aafl I* Uiite to lie prevented t 



CORRESPONDENTS. 

SrvKi. BAkj Are magnoUAed h)- Mr C. II. CoIUm, SL. Litle 

St7«cL 
J. G. — 1'he cenioiil be wlibex for u Pliwtor of Paiii. 
Omxikitii. — Full dtrecUoTu fur Aiulyait of Minerals are cf*ea 

bi Vni. I. 
J H. < Moocheeter).— U li only mslMd and poured laba 

pill •boxes. 
MAycnnsniii.— Blmnitli and nil other niplali may be bought 

the oonier of Browalow Street, Drtiry Lum, abo Id SImc 

Lane. Blnnutta Is aboat U Od. mt }>oiinri. 
J. Bali, ihall be attended to aa <>arly at )Miulblo. 
W. B. (Leeds- I'We really camnt soy bow many volume* 

our worli will extend to— «^'ery arUcle is coroplato In lUtlt 



ConuntuUcaUani, Boodt for RifvLewr. InvrnllAiu tvr 1Uaa> 
tratlim. inc.. to be addressed tu the Editor. S5, Grast 
Prcecot Street: to Uie i^nnlBi: or lo tbe Publtsber. All 
LcUers nttul be post paid. 



Priated by D. PsAitcn. t. White Hone Lane, Mile End 
Published every Saturday by W. Batrrani, II, PatrmoelBr 
How. sad may be bad of all Dooksallers and Hewuoen in 



Town and Countc)'. 



THE 



MAGAZINE OF SCIENCE, 

Mnn ^r!)ool of ^rt0* 



No. IJCIV.] 



SATURDAY, JUNE 20, 1840. 



[Pricx Hd. 







PRACTICAL MANAGEMENT OF BEES. 



Ctf ^ practicml maoagement of bees, the formation 
nidn ■mogeaieDt of the Apiary is of BOoie im- 
fOrtnice. Tbe prime requisiteit arc tht^Utr from tbe 
wttwrw of heal and cold. anU quiet. Facing 
llMlh*«rdi>, the luTiM ahouid be carrfully screened 
fcwR ll»e north and north-east. A grouj> of yoanj^ 
or a cloAc-growing hedge. wiU auswer tbe 
reU ; or adTantage maj bs taken of a raxige 

XOV, II. 



of baildinga, or a ^rden wall. In arailing ottr- 
Bclrei, however, of the shelter of bulldiug?, cm 
rausi; be taken to keep the hires at such a distance 
as to be clear of the raJn-drops, and from the 
eddying wiiidf cauEcd by such a locality. A dis- 
tance of not lcs« than eight or ton feet should in. 
terveae between Ihem and the screen ; and of tiiia 
space the balf.breadth nnt the hives should he laU 



00 



MAGAZINE OF SCIENCE. 



with floe puTcl, to ftl}snrli Ihr moistnrr. Kn<l keep il 
free from weeJs, grnfls, stnivrs, &t:. 'ITie »jiiire of 
ground bctwfieo aud in front of the bives, to the 
extent of at least three feet, eboald be covered in 
the some manner. 

Qnitt is ctKodaUy necestar; to their doing well. 
Beea do not thrive in tlie near noighboorhood of in- 
cessant noise. The apiary, therefore, should be at 
% distance from smithies, mills, steam engines, Sec, 
attd also from such manufactories as emit noisome 
■mells. When ctrcamstanctri) will admit of it, the 
apiary should be placed lo new from the windows 
(rf the family titting-room. This will save much 
of the trouble incurred in watching at swarming 
time, as well as giTo greater secaricy from marauders. 
The hiffes should be elevated about fifteen ioches 
from the ground, on a tingle po*t or pedestal, in 
preference to tijree or four, which is the usual 
number. Vermin are thus prevented by (he pro- 
jecting edge of the floor-board from climbing over 
and reaching the entrance. It may be tatd down as 
a good rule to have thi- hives placed aa far from one 
another as the extent of the apiary will admit. 
\\'hen standing at intervals of only two or tbrre 
feet, the bees areyery apt to quarrel amongst them- 
■elves. They sometimes mistake their own proper 
domiciles when Coo much crowded together, especi- 
ally when hurrying homewards in the working 
■eoson. or hastening to escape a shower, and the 
mistake is attended with fatal consequences, la 
feeding a weak hive, a close neighbourhood is parti, 
cularly dangeroua ; tlie smell of the syrup is quickly 
difTuiied over the whole colony, and pillage generally 
ensues. In swarming, too, when the newly departed 
emigranti are discouraged by a sudden blast or 
chnntrft of atmosphere, mid the queen hastens to 
return to her old abode, her ignorance of the locality, 
having, if a young queen, never been abroad before, 
renders her very apt to mistake and enter a hive 
where she is by no means welcome, and the swarm 
following her, a bloody conflict takes place. 

Wlien the apiary is situated in a garden, there 
will be no want of bushes and low-growing ^rubs 
on which the bees may alight when swarming. But 
when it is located on a lawn or smooth level, the 
swarm is pxtreraely apt to fly off altogether, or lo 
take up its ntation on some high tree in the vicinity, 
from which it is difficult to dislodge it. A few 
ever-green shrubs growing in front of the hives, and 
at a few yards disunce. will prevent this. Or if 
auch an arrangement be, from particular circum- 
stances, not expedient, the evil may Le so far reme- 
died by sticking into the ground, near tlic apiary, 
some branches of trees, retaining their foliage, about 
the period when swarming may be expected, Watfr 
is essential to the operation of these insects duiing 
spring and summer ; a shallow pebbly stream in 
the vicinity will, therefore, be most odvantageous, 
where they can drink without danger of drowning. 
Its absence should be supplied by artificial means ; 
and n nhallow vi'Asel of water placed in a secluded 
and quiet quarter of the apiary, having a few smooth 
round stuooa thrown into it, of a siso to project 
above the surface, and ailonl footing to the drinkers, 
will answer the end. The neighbourhood of large 
ehctU of water, however, or of broad rivers, is in- 
jurious ; Uie little forag«n. in crossing dariug hiKh 
winds or dashing rains, perish by liundreds iu a 
single day. 

Covered apiaries, or bee-houtea. ore common in 
England, and are sometimes, though rarely, met 



with in Sfsotland ; iher have their advantj^ea, bd 
are not withoutserious drawbacks. They aiTord riirii 
ter from the ejctremcs of heat and cold, and, 
properly conatractcd, are also a complete proteeCioa 
from thieves. But when the number of tims l| 
great, the expense of anch stmciunea is ao 
siderable as to preclude entirely their being broofhfe 
into common use. Besides, their confined timiti 
render it necessary to place the hives quite close t 
one aootber— 4U arrangement which we have already 
noticed aa a great evil. And, ftuolly, in operatiiig 
experimentally on any particolar hive, the wfaaii 
colony is apt to take the alarm, and to cause a dft< 
gree of confusion most inconvenient to the cperttMr. 
A good thick coat of oat or rye-straw, if the hivci 
be of that material ; or, if of timber, a well-seasoned 
and painted snrtout of fir-plank, three-fvurths of a 
inch in thickness, resting on the floor-board, 
having a vacant space of an inch between tt aodthl 
hive,, will be quite sufficient security against thi 
extremes of heat and cold, while rain may \n 
warded off by thatching the hive, as is shows is 
Figure 5. 

Nivet are found of almost all shapes and aixa. 
and of various materiala— circumstances influenced 
sometimiv hy convenience, hnt oftener by tlie 
and fancy of the owners. In France, particularly, 
where the culture of the bee has been much at- 
tended to, the variety of hives is very great ; bof 
with few exceptions, they appear to be rcmarkab{| 
deficient in simplieity. 

Straw Hivex, of the common bell-shape, with ■! 
their imperfections, will continue tn use, becatiM 
they are easily made and cost little — because thd 
handling of them requires little skill — and becaasei 
us long as the suffocating system is persisted in, (hej 
answer the purpose well enotigh. It woold ba 
desirable, however, that more pains were bestowed 
on their form. To concentrate the heat — to retain; 
it, and thus to accelerate the hatching of the broodi 
on which ao much depends, no shape is so well 
adapted as the globular. We would therefore re« 
commend straw-hives to be wade in the form of $1 
glol>e, having the third of its diameter cut away* 
(See Fig 1.) Two rods or sticks of three-foorthx 
of an inch in thickness, forced through the hive at 
right angles to a line drawn from the entrance, and 
about an inch higher up than the ceatr«, will b4 
BuflGeient to support the combs. 

midman* t Storied Straw Wire.— Tlus ia pre* 
ferred by many to wooden hives on the same plan, 
from the persnasion that straw is a preferable mate- 
rial. ' It consists of two or more stories, each 
inches in height, and ten inches in diameter. Iik 
the upper row of straw, there U a hoop of abooC 
half on inch in breadthi to which are fastened 
or seven wooden spars, each one-fourth of 
inch thick, and one and a quarter of au inch broad, 
and half an inch apart from each other. To these 
bars the bees 6x their combs. In order to gtw 
greater steadiness to the combs, and prevent their 
beiui; broken or deranged when the luve is movedt 
a rod ia ran through the middle of it, in a direction 
across the bars, or at right angles with tliem. A flat 
cover of straw, worked of the same thicknes* as the 
bive^, and twelve inches in diamrter, is applied to 
the uppcrmoHt atory, " made fast to the hive with a 
packing-needle and thread," and carcfolly lutod 
Before it is put on, a piece of clean paper, of the 
slae of the top of the hive, should be laid over «he 
bars, tho design of which is to prevent the bees fVom 
working in the intrrveniDg spaces. (Soo Fiy. 2.) 



MAGAZINE OF SCIENCE. 






GrtHmn /fivf. — This has long been in use in the 
Greek Islands, nuil is sometimes called the Candiote 
HJTe. Ic is In the form of a flower-pot, open at 
the top, and provided with a flat corer in the sacDe 
Msnotf as the hire last described. As in this last, 
tb», « oertaio number of bars ire fastened to the 
Uppannoit ruU of straw, each desigurd for the foan- 
Attioa ol a comb ; and when pre|Nued for use, the 
wrer is Laid above these bars, fixed at the edges by 
wooden pins, or sewed with pack-thread, and having 
Hk* joining carefully plastered with clay. (.See 
Rg. 4.} Thi^ bive affords considerable facilities for 
ing the bees to work in wax. It is only neces- 
to remove one or two of the eombs, and the 
will immediat<!ly commence tilling up the va- 
in this way» a portion of their honied 
y be abstracted without difficulty, and 
■iUKist having recoarse to the barbarous practice 
«f aiUfocatiotu It aflbids aLao the means of mak- 
Im arti&aal swarmi. It will be observed that in 
aecMcqueoce of the diameter of the hive gradually 
diminishing towards the bottom, rods inserted 
Omnigh the body of the hive are rendered aoneres- 
cary, the wedge-like form of the combs serving 
uificicntly to support them. " The hives,'* says 
Vhcelcrr in his Journey into Greece, " are made of 
villows or osiers, fashiouvd like our common dust- 
basJtets, wide at top, and narrow at the bottom, and 
■bstcrcd with clay or loam within and without. 
nue Copa are covered with broad flat stioits, which 
arc alao plastered over with day ; and, to secure 
them from the weather, they cover them with a tuft 
9t strsw M we do. Along each of these sticks, the 
faatcw their combe ; so that a comb may be 
oat whole, and with the greatest ease imagtii- 
thle. To iacrea&c them in spring-time, (that is, 
by make artificial swarms,) they divide them, first, 
u^ the sticks on which the combs and bees 
-ncd from one another with a knife ; so 
uitni: out the first comb and bees together on each 
liAi, t2k«7 put them into another baslut in the same 
vder as they were taken out, until they have equiklly 
Abided them. After this, when they are both again 
•ecommodatcd with sticks and plaster, they set tlie 
m basket in place of the old one, and the old one 
baome Dew place. And all ibis they do in the 
^h^ldk of the day, at such time as the greatest part 
^^^^&c bees are abroad ; who, at their coming home, 
^^Hkowt uuch difficulty, by this means divide tlicm- 
^^^Mi equallv. In August, they take their boacy, 
pHbh thefma in the day time also, the bees being 
flereby, aay they, disturbed the least ; beginning at 
Ae mitilde, and so taking away, until they Imvcleft 
V of combs in the middle as they 
nt to maintain the bees in win- 
''I'lug luase bees that are on the combs 
bosket again, and covering them anew with 
:.l tiliinter." 
' — Thereiipective merits ofatraw-hivea 

ana ' have often been made the subject of 

Aicwaioo* Certainly those of straw have a decidrd 
•^erlority over thusc of woml, tn respect to their 
cipahility of maintaining an equable tempcrntarc, 
from the non-oondncting quality of the material of 
•kicb the former arc constructed. The tatter are 
■OR easily kept clean — they funiish better means 
if dtJience against vermin — tbey are a great deal 
■ore durable, and afford a much greater facility for 
eiMrating cxperimenloUy, and studying the nature 
•f their interesting inmates* And what is always of 
Vaortaoce in matter of rural economy, their cost, 
ift ml M icsanb th« aiiopUr kindsi ia very Utile 



more than tliat of the itnw hlvei } and If we take 
their durability into account, it is actually less. But 
the nnture of the material of which they are made, 
rendering them easily affected by variatioDs of the 
external temperature, fumisbes an important and 
well-founded objection ; ftir notwithstanding all the 
precautions used, no practicable or manageable 
thicknesa of material, nor wrappings of straw ropes 
and straw covers have been found effectual in re- 
medying this defect. Therefore those who cultivate 
heea for the sake of tlieir produoo only, and who. 
have no particular desire lo study minutvly their 
natural history, or to witness their proceedings in 
the interior of their dwellings, will do well to adhere 
to hives of straw. 

There is a greater variety of form and stractnre 
in the wooden hives, than in tliose of straw ; but 
the !>toried kinds, of vanoua ilimensions, arc most 
gone rally used. 

It is quite immaterial of what shape these boxes 
are, provided the safety of tlic beea, and the con- 
venience of inspecting their operations and taking 
their honey, be nt all times regarded in tbar con- 
Btniction. So also to describe oven a small part of 
what are found so varied, would be at best, imper- 
fect and unsatisfactory. They may be made of a 
single box, as represented in Pig. 4, or consist of • 
great number united ns in Fig. 6. Though to the 
latter construction is the same objection as tliat 
made to the too close approximation of hives of any 
kind. Some part of a wooden hive should at aU 
times con»:ist of a glass window, covered, however, 
on the outride with a shutter ; the use of this win- 
dow is to enable the master to inspect the inside of 
the hive, that he may judge of its state, as to its 
fulnc-ss, and the liealth, activity, and swarming of 
its inmates. 



RESEARCHES ON CHARCOAL, 
nr V. CBBuviiBuasB. 

Men of science, both ancient and modem, have 
published a great number of works on the proper- 
ties of charcoal, and notwithstanding the extent of 
their researches, tlic most of their labours are in- 
complete. 

In considering charcoal with respect to electri- 
city, they have remarked that some charcoals give 
B free passage to that fluid, while others refuse to 
transmit it ; but they have not analyzed the cir- 
cumstances of this phenomenon. 

Do the other hand, charcoaU have been regarded 
in general as bad conductorB of caloric ; neverthe- 
less, experience shows that there is a great difTcr- 
CDcr between tliem in this respect. 

If the labours undertaken on the hygrnmetric 
properties of charcoal are examined, it will be seen 
tliat they have not been pursued. 

Tlw combustibility of charcoal hns been studied; 
but the resuitu presented leave much to be desired. 

The state of imperfection in which our knowledge 
of charcoal is found, at present, has led me to sub- 
mit the properties of this combustible body to a 
new examinaliou. 

Charcoal may he found in two states relative to 
its foculty of conducting electricity ; the same takes 
place with regard to its power of conducting caloric, 
and the same sort which conducts electricity likewise 
conducts caloric. 




MAGAZINE OF SCIENCE. 



Anally, cbarcual frum the Mue piece of wood 
will be found more or Ipss corabuatiblc, accoriling 
Co its state of carboniutioo. 

Carbonha/iort. — If two pieces of wood, prodnced 
by the SAiDC hrnncb, betaken, and snbmitled to dis- 
tillation In a retort of stone-ware or porcelain, until 
no more vaponrs pass off, two pieces of charcoRl 
vill be produced of the same naCttre, and ia the 
same state of carbonization. 

If, after Ihtft first carbonization, one of the pieces 
of charcoal be replaced in the retort, and be heated 
to retlneas, from these two operations two pieces of 
clmrcOBl will be obtained, which will possesa verjr 
different propcrtiea. 

AU sorts of light and hear j wood that conld be pro- 
cured, both native and foreign, submitted to these 
two distillations, have given charcoals which pre- 
sented the same differences. 

Charcoals from aniinai substances, produced hj 
a first (HstiUotion, could not be made to change their 
state but by a violent degree of fire. 

To change the property of vegetable charcoal, it 
WM sufficient tu make the lire red ; the method of 
applying the heat is IndifTcrent. Whether the ope- 
ration is performed in close ?c8scU, or in the open 
air, the result is the same. If it is effected by igni- 
tion the mode of extinction is equally indiifcreot. 

In geDcml, charcoal rany be found in two oppo- 
site states, resulting from the intensity of the beat 
which haa been applied to them during their pre- 
paration. 

Conductibiiity /or ElfrlricHy. — It has been long 
cince remarked, that among charcoals some had the 
proi»ei-ty of tnuifimittitig the electric fluid, but the 
study of the circamstancea which accompanied this 
faculty has been neglected. 

In the experiments which 1 am going to recite, all 
the charcoals in their first state of carbonization, 
and which arc uewly prepared or dried, do not 
conduct electricity, and they do not become con- 
ductors but when they hare undergone the action 
of a ftron^jT fite. 

A fact which it is important to notice is, that the 
ciharroal which is not a conductor docs not derelope 
rlcctriciiy by its contact with zinc or iron, and 
when it is a conductor it produces electricity by 
this contact. 

Tlie conducting property of a cliarcoal for elec- 
Iridly may therefore be raried by the contact of 
zinc or of iron ; and this simple method is even 
preferable to others, since, if the non-conducting 
charcoaU are humid, they transmit electricity ; 
wherefore the application of one of these two mctuln. 
and priuclprilly of zinc, will be the method which 
we will use to ascertain the state of conductibility 
of a charcoAl for electricity. 

If charcoal which is to be examined is in a state 
of powder, it may be made into a paste with gum 
w^ater, and a Ubltrt may be obtained wliich may be 
tried with facility. The only precaution to be taken 
is, not to add more of the mucilage than ia necessary 
for making tlie paste. 

To A chorconl in the first state of carbonization, 
the faculty of conducting the electric fluid at one uf 
its points may be given, by making this point red 
hot. Tliis experiment is easily performed by 
heating a small cylinder of charcoal at the flame of 
a candle : when it becomes red it Is to be dipped in 
water. If it is then tried, it will be perceived to 
hare become a conductor of eleriricity. 

Tlic best conducting charcoals whicli I hare k 
yet been able to meet, are those which have eiicaped 



combustion during the reduction of ore io tlie high 
furnace, and which are drawn out ah)ng with the 
slag. 

From these results we may range all thea« ehar- 
coals into two great clasoea, — charcoaU that ore 
conductors of electricity, and charcoals whidt wve 
non-conductors. 

Conduct ibilit If for Catoric. — Nothing bos yet 
been published on the conductibility of c&lonc ; and 
this combustible body having been known to prcacnt 
the greatest resistance to tliis fluid, has beea named 
a bad rmtductor. ITiis error bos arisen from iU 
having been believed that charcoal only existed in 
one state ; but the experiments which follow prevo 
that Bome charcoals refuse to conduct caloric, while 
others transmit it with sufficient facility ; and it is 
extremely remarkable, that the charcoals which are 
conductors of electricity are also e^iually condaetore 
of caloric. 

If a piece of charcoal be chosen without cracks, 
and without knots, of a cylindrical form, abovt 
three lines in diameter, in the first state of carboni- 
zation, and that one of its extremities be uxpcravd 
to the flame of a candle, the heated part will entrr 
into combustion, and the propogation of the heat 
will not be sensibly extended beyond the port 
immersed in the flame. 

If the same operation is repeated with a cylinder 
of charcoal, taken from the same wood, in the 
second state, and consequently a conductor of rlee> 
tricity, the effects which will be observed will be 
different ; the caloric will be immediately transmit- 
ted from one end of it to the other, and the sensa- 
tion of hcttt will iKCome so great that tingera of any 
delicacy would be unable to hold the charcoal in the 
experiment. The extremity placed in the flame 
will moreover be obscrred to grow red, and not to 
burn in so decided a manner as in the first coao. 

The theory bad before poioted out that the effecCv 
observed should thus take place . in the first ex- 
periment the accumulation of tlie caloric increased 
the ignition ; and in the second its transmission 
oppoaed the inflammation. 

These simple cxperimeuts may show the difference 
of conductibility between the two sorts of charcoal ; 
but OS they do not seem sufficient for naturalists 
accustomed to the most scrupulons researches, I 
have made use of the little apparataa wUch I wa 
going to describe. 

To make this experiment, a vessel of earthen- 
ware, or of wood, may be used, the sides of which 
are of equal thickne,«s. These sides should be 
pierced with two holes, from 0.015 metre to 0.029 
in diameter, for the reception of two charcoals of 
the same dimensions, the length of which should 
1>e exactly equal, and which should only difler in 
their state of carbonization. 

The external extremity of each of these charoooli 
should be hollowed, to receive the bulb of a 
thermometer, which should be kept in contact with 
it, and should be supported iu a horizontal pontioa. 
The vea:*el should then be filled with mercury, the 
temperature of which shouM be near ebullition. 

The result of this disposition must be, that the 
two charcoals would be in the same circumstances, 
fuuce their interior extremities ore exposed to the 
same source of caloric. 

In one of the evperimcnta nude with thia ap- 
paratus, on employing two charcoals of poplar, 
one in the first state of carbonization, and the other 
in llic second, and on using two Ihermomrtcrs 
marking 20*, ^Raaumur.) before the operation, I 



MAGAZINE OF SCIENCE. 



(^Mtcrred ihmt the themiometer, applied to the 
charcoal in the MCOQtl itate, rose rapidly from the 
iulant that the vessel was filled with mercury, 
irhU>t the othtrr was fetntionary, aitd thsC it few 
XDitftDts aftcrwnrds it indicated .IK', that of the 
diarcoml ia the firat state of carbooizatiuii being 
»ti)( At 23'^, that is to any IS" below the first. 

rbe ihermometer, lod^d on the charcoal in the 
•MOod atafe of cirfooniuitioti, arrived to itj^ mirxt- 
m^tm of 40", while the othtr. after a long intrrval 
of linjc, did not rise beyond 25*^. 

II'"- InKt exjterimrnt leave-s no doubt reapeetiiig 
rHoce of condactibility of the two charcoals 

■ rjc ; and it proves besides, that the charcoals 
mhtKh axr condoctora of electricity are equally 
conductors uf CAlortc. 

Dnuitf. — It is known that. the specific gravity 
flf rharcvnta in general arises according to the 

1 .„ „f Ijjp wood from which they arc made; 

*• course of my experiment£ I have always 

■ 1, that those of e<iUQl weight in the first 
itate of em-lion ixation had constantly a greater 
bvlk than those in the second state, that is to 
mj, vfaich had been prepared id the cootrary 
dRsmstJuioea. 

To verify this first perception, I exaniiaed the 
d«a«ity of chan^nnU nf htack alder in their two 
ifartKft. To effect this deaiga, I weighed equal 
•Ohunea of the charcoals, divided to the same 
tbidcnets, and in the two states of carbonification 
tiresdy recited, and found that the density of the 
e^rroal of black aider, in the firjtt state of cnrboni. 
■tioDp ia to that of the charcoal uf the same wood 
h iKe Koond state, as 4 is to 3. 

I then took charcoala of the extreme limits of 
douity afforded by those lu my posaession, that is 
ta aay, poplar and guaiacum ; the woods of which 
W) for their respective densitiea 0.3012 and 1 .3132 ; 
bol instead of wetghiog them after I bad pulverized 
iheBB, aa in the ftrst case. I took their weight in air 
^ in water, in determining the tjuantity that they 
^k^rbed of the latter, and I then obtained the 
^^^bwioff results .- — 

Vbnoal of poplar, — lat carbonixation 0.12372 

2od carboniiation 0.16743 

OhiROalof Gaaiacnm, — 1st carbonization 0.fi8t78 

2nd carbonization 0.84^29 

Trom this table the consequence may be drawn^ 
tbat of Light wood, that of poplar for example, the 
c!arco«l in the first state of carbonization has a 
Anaty two-thirds of that of charcoal in the second 
tfllr oif carbonixAtion ; whilst for the more compact 
WMda. voch as that of guaiacum, the density of the 
ffesfeoal in the first state Is a little above three- 
Ibwlks of lltat of the charcoal in the second state. 

Theae experimenta prove, moreover, that char- 
coala nrrpared 5Y)m the same wood may be, with 
Rfiani to their density, distinguished into two 
rtaaaer, and that the most dense charcoals are those 
mhiA are eotkductora of electricity and of caloric. 



THE MYBIAMOSCOPE 

b a modification of that well-known instrument, 
tbt KjUaido»copG. Although the latter produccH 
fti most braatiful patterns imaginable, yet on the 
tf^l^itaat abake, (which can hardly ho avoided,) 
lb reflections vanish in a moment, never more to 
W Men. to the freai mortification of the artist 
vko mftj be ondeftTonring to copy its Protean 



shapes, and the instrument in its present slate is 
little belter than an uptiral toy. If some moans 
could be adopted to throw its beaiilifnl figuifis on 
a screen after the manner of a nmKi*-' Imithoni, it 
would then ftirntsh designs ad tnjinitum of tlie 
preatest use to carpet manufacturers, &c, — Thia la 
accomplished by the myriamoscopc which is thua 
conslnirted .— 

Pr'xrure two pieces of lookin;? gloss of the same 
aire, A A. join them together iw nt B with a strip 
of leather, which will act a^ a hince, so that the 
mirrors may be put to any aiiple required. Place 
two roIMrs beneath on which ofHx a piece of calico, 
D, which may be rolled off one and on to the other 
by means of two knobs or other contrivance. On 
the calico paste ornaments of various descriptions : 
those beautiful borders and flowers fumisned by 
papcr-h suffers are very suitable. It is rvtdetit 
that whatever objects may come in contart with 
the mirror, will according to their inclination form 
the most bcAiUiful designs — a Amall fragment of an 
omament will form a ccntro-pieco, and a part by 
reflection will produce a whole. 




The mirrors should be so adapted that they may 
be put to any degree of inclinaiiou. by means of 
two small slri[M of wood aflixed to them and 
reaching througli the sides of the box. The top 
of the box may be in pari covored with a piece uf 
muBlin, or some scnii-transporent subBtancc, in 
order to admit the light, and an aperture shonld 
be made in the box to roceivo the objects. 



LITHOGRAPKT. 

LiTRoonAPiiT is founded on mutual and chemical 
afliutties, which hitherto had never been applied 
to the art of engraving. Tlie dislike which water 
has for all fal bodies, nnd the aflinity which all 
compact calcareous stones have both for water 
and greiuy substances, are the bases on which rests 
this highly inlcrcsling art. 

The art of lithography may be divided into 
two parts : 1. The execution of the drawing ; 2. 
The printing. The former requires but little 
practice, as any person who undorstands drawing 
may meet with success : the latter is filled with 
diiliculties. 

The first part consisttf iu drawing on a atone, 
( which has been previously made perfectly level 
and smouLh,} with au ink or chalk composed of 
greasy materials, in the same way one would 
execute a drawing un paper with ink or coiumoiL 



on 



M 



MAGAZINE OF SCTENCB. 



eliftik : the second consuU ia taking libe Moac, u 
riM'eiTed from the drafUmui'f hftodt. and obtein- 
iiiH; laipiTKiions from it, u od« vnoM from a 
copper-platc. To obtAin these inprcMiou, the 
lilbwi^phic [iriotcr wets the whoU mttUcc u( th« 
stoDe ; but as th« gittaiy cbnlk, which constitatet 
tlie drAwing. bu a. Dttonl nvenkw for wnter. 
those nnrta of the ft4Me aUme whkjy u« not 
covered with the chalk iinbibe it. The printrr, 
while th« atone it atiU wet> puna a thick 
and ip^casy iak «Ter iti wholt muOtce v and 
tho greaaj Ifaies of the diavuif ncviTv the 
ink, while the wet surface of th« Mone Mftinca 
to take it : a sheet of pnper is now aliottgly 
pressed on the stone, which, recciTtnf the priatiiig 
iuk that has b(?cD applied tu lh« drawing, gives a 
reversed faG-«imilc of the ong;iital one : the atone 
is wetted afresh, again chuged with ink, and 
thuH a Bohcs of impreasioni are obtaioed. 

In the above descriptioD cooaiatj the whole art 
of liLhography, 

The s&nie result is obtained as in printing from 
copper-plate, but by diffcrtmt meaoa : the process 
of engraving is entirely mechanical, that of Uiho- 
graphy entirely chemical. 

Compotndon of Ink*, — This haa been prrpsxsd 
with grease, mixed with essence of tnrpentine, 
and with resins dissolved in apirits of wine : th« 
prcfcrcnco i*, however, given to greasy and 
resinons substances, combined with alkalies. 
Amongst the numbcrk'ss recipes for making 
lithographic ink, the following appeaiB to b« one 
of (he beat ; — 

Tallow candle, 2 otmcea. 

White wax, % ounces. 

Shell-lac, 3 ounces. 

Common aoap, 3 guiicM. 

Lamp black 

Soap ia the only of ilio above components of 
which the proportion must never vary ; it is des- 
tined, by lite alkali, which it conrains, to render 
the other ingredients sohiblo in water. 

It is nccrsnary, iu order to mix the above in- 
gredients, to hnve an iron saucepan, with a covef 
that closes bcrmeticAlly. The wax and the tallow 
uiubt be put in, and heated until they catch fire: 
while thoy are burning, the soop, (which has been 
previously cut into small bits) must be thrown in 
separately, and stirred the whole time; but a new 
piece must not be thrown in before the furmor arc 
melted. Tho whole of the soap being dissolved, 
they are allowed to bum until reduced to the 
volume iliey had before the auap was put in : 
great care, however, must be taken not to bum 
it too much. The shelUlac is now added, and the 
flame cxtinguised, if it has been possible to keep 
it lighted during tho whole operation, as it is oftoo 
RceeastTy to extinguish it in the beiriuning, and 
take tho saucepan off the Cre, to hinder the con- 
tents frfim boiling over. The flame being once 
put out, if all the suhstoncca arc not cuuipletely 
melted, they must be didsoWcd by simple ebullition. 

A amallminntily may nowbepuluuacold plate; 
if it works brlwcen the linprrfl like wax, it must 
be burnt a Utile more; but if, after it is quite 
cold, it is broken in two, and the bits will not join 
on being pressed with the Angers, about a dram of 
soap must be added to tlic mass in tiie aaucepan, 
and, the moment it is dissolved, the flame put 
out. 

It when cold, a piece of this ink is dissolved 
with water in a saucer, by rubbing, as one would 
Indian ink; aUhuU£li at Grst it appears but little 





tzidcnod I* iTiwilv^ ii wsS a& taua mis ««k tks 
voter, lad tmm « pvjM ^^ Jtmf lifaK. 

The ink bffooghi t» this gteic eC fcdnotMs, nft 
(he aanecBSB «pe» a rioFV k«, asd add aovw we 
Ump-bUck : it vfl an hv ohsenod, thai iW 
mew black isf«t ia, dw mmi mIbU* in vaiai iht 
ink will be. Tm m^ bfadE. Ww«rer. woald 
apoOit; fsagh—iy iigiaci— ttowakeUb4adi,. 
iaatead af thi U^hm^ m Btmak eaiag m^if^ 
it had bedfv tka&ik «H fM M. 

TheiiAisi*la«kp^^i mimtytUhmU 
caM in pnpcf nj1iiiiiin> mmiku ts canni|DM» «r M 
• slab of w a rb ls ( fia i iwrij mbfcnd latiih wp)| 
aud« whenitbvfiaatoeooCaBVMMBdbyaaoaM 
picee of aaiU* sff MOBS laid ifM a ; ii in hMlty 
cat into nqnarv bits, At ladfan iak. Thia com* 
poiitum k of the Vklitf ^■liaiiii to iiiiwirr 1b« 
success of the diiwiiiM csncatai ia nfc. U aan 
be aimiUr to Indiaa iak, fioH viiek n diffcfB aa^ 
in wei^t ud ku^iMk bat of whlKk it 
have the inctvn» tba bdUiMi 
•olability in water. Is cmb 1^ 
not been oompietely aocfiM^d, tht 
the means of •ocrsctiim >— 

To JUmtedf D^eem t^ tAe Smk.'-Thn ink 
soluble. — Add soap. 

It u soft, and attaches itsaU to. (ha 
Bum it more. 

Some lime after disaolring itia water, it 
thick and slimv, and reqnim n 
of water in order to be eaablod lo draw 
This ia the dcfacl of almost aU inks . it 
from iu being insnfficiently bnmod. Bom it 

The ink is not compart, and la fiiU of fanbblea. 
— It has been cast too hot on the aurble slab i 
cast it again when it ia less hot, and laj a heavifir 
stone over ic 

The ink has no tenacity. It seems composed of 
acorias. — Both these defects proceed, either f wBir 
its being too much burnt, or from its con 
too rouc^ black ; in cither case add equal 
of wax and soap, and mek on a slow fire. 

In all this manipulation, it is sai&cient to 
been informed of the qualities reouisitc to 
tote good ink ; and that the resdersnould re 
that, unless the contents of the nncepan be 
to a coal, Ihe composition cannot be qwiled ; 
that it is sufficient to add more or less wax and 
snap, or burn more or less, according lo the judg* 
ment of the person, and the state of the ink, to bt 
sure of ultimate success. 

CompoMition of UUiographic C/io^.— Chalk, ta 
be of a good quality, must be Arm, wiihoat b^nne 
hard, and must attach itself to the ston 
clogging. The cutlioga of the chalk mu5t i . 
solves into spirals, like wood shavini:*, :iii>i 
texturemtut De close and homogcDeuus, like 
of wax. 

The composition of dudk is atill more orb 
than that of iuk : more or less soap, wax, or 
may be added at pleasure, as more or leas 
tion may render these dUferent proportiuiia of 
importance ; and, as the eifcct of the caleina 
in a given time varies, accurding to the inteuaily of 
the flame, it is preferable to indicate, ofi we have 
done for the ink. the dilfercnt defects that chalk, 
may have, and the remedy. The reader may easily > 
imagine that it is impossible to give certain Tuie» 
for making chalk, when he is assured that itia] 
>ery ditPicult. even with great practice, to mako > 
twice following the same chalk : Uicie is always 
aome alight dijTcreuce. 






' ^< hnYB been maJe with bilnmcn and maa- 

-' they were too friabh?, and did not adhere 

Til inr ftone ; an addition of v&x wa^ found nc- 

tfnary Xo bind th« incredtvnts toj^tber. It mufll 

tL»- r..r,f.«..-.i_ however, that the chalk hitherto 

'uho^flphy is far from being perfect ; 

. has the defnrt of being too soft in 

(. It is very iropoitant to keen the chalk 

1 with glass stopppT^, as the least damp 

I'.TT the nature of it. 

Common soap, 1 ounce and half. 
Tallow, 5 ounces. 

White wax, '2 ounces and half. 
Shell-lac, I onnco. 

The wanipuUlion of the chalk is Ln ever)- 
mnrct similar to that of the ink, with the only 
' -^ r t;,c that a few drams of wax (instead of 
'-'{ soap) are thrown in, at the end of the 
. 'n. The burning nni«t be stopped aa soon 
u the chalk, when quite cold, breaks with a sharp 
snH tlftn frncture, and resists strongly Ute nres- 
ninsrft. Less black is put in the chalk 
ink; it is qutto sufBi-ient that the 
mark easily on the stone. 
. is t'jo soft, it must be burnt again ; 
a little more wai be added ; if filled 
, it must be cast hot on a marblo slab, 
^imullcr, and melted again with a 
; al ; lastly it must be cast in a mould, in 
( must bti strongly pressed ; fur the heat of 
■■"'^nds considerably the composition, 
' this precaution taken, it might still 
I pores which would destroy its com- 
pactiMSA. 

U a mould cannot be procored, the chalk mav 

b« owl in a amall linen bag, previously lined witli 

taae paper, well rubbed with soap ; it must then 

^- -^-t! pressed with a weight or stone placed over 

. :- chalk must be taken out of the ba^ be- 

- .8 quite cold, and cut in bits of a proper 

ikri'-t, «ithcf with a mould or a knife and ruler. 

(Jb be continued.) 

iCnOK OF WATER ON MELTED GLASS. 

Ma. PaiLKES, in his Essays, had adverted to some 
ifyaianees produced by water flung upon gloss 
«b«a in the furnace, which appear extremely 
ifeaag«, alilioui^h they were related to him by the 
«ait vnditpuled authorities. 

if a small quantity, even 6 pint of water, were 
Id b« thrown into a crucible of gloss in a melted, 
flr fmlber melting state, while the scum or sandiver 
If >poa its snrfiKCD. the water would be converted 
tMUntly into steam, so that an c-Tplosion would 
ti4c pUoe : mad if Cbe qoantity of water were more 
lirable, the furnace would probably behtown 



Bat what tbfl sandiver has been teummed otT, 
md tke gfass in qniet fusion, if water ia thrown on 
It, the globules dance npon the surface of the 
gliiM for a considerable time, like so many 
of quicksilver upon a drum head, while 
ilrvairotT is beafciBg it. 

r iiowever. a similar appearance to this 

U« in iron; for water evnparatei 

i,^, ; A pUt« of iron that is heated to red- 

B only, than from a plate that lias been brought 
»• wdbdnog heat, or very nearly to a hcot necessary 
it. 

in th« msonfaetore of Mack bottles, it 
[y bsppeoa that, while the workmen are 



oraploycd in monldlngand blowing the bottles, that 
the glass, or metal as it is colled, becomes too cold 
to work, so that thej find it necessary to desire the 
firemen to throw in coal and iocreaae the heat. 

This, however carefully it may be done, wUl 
aomedmea produce lo much dost chat the surface 
of the glass becomes covered with coal dust. When 
this accident occurs, it oocaaions such a motion 
within the melting pot, that the glass appears aa if 
it were actually boiling ; and if the metal was osed 
In this state, every bottle would be speckled 
throughout and full of air bubbles. 

Now, as it would be Tery inconvenient to wait 
for the whole of this coaly dnst to be consumed by 
the fire ; and besides, it might occasion the glase 
to boil over the edges of the melting pot, the work- 
men have to endeavoor to discover an easy and 
eiTectnal remedy for this accident, and this remedy 
is no other than common water. 

Whenever this ci rcunistance takes place, the 
workmen throw a Uttlc water into each of the 
melting pots. This water has the effect not only 
of stilling the boiling of the gloss immediately, but 
it also renders the melted metal as smooth and 
pore as before, 

Mr. Farkea considers this cnrioos and almost 
instantaneous effect, as probably owing to the 
water becoming decoropowd, and affording its 
oxygen to the cool dust, and thus converting it 
into carbonic scid gns, which immediately escapes 
and is dissipated in the atmosphere. 



COLORS FOR PAINTING ON VELVET, 
SATIN, SILK. &c. 

Afenttrum. — Dissolve three or four pieces uf gam 
tragacanlh in a tea cup full of hot water — strain, 
and add a little of this lo the colors, when you 
lighten them for a hut coat or ground-work, 
otherwise the colors will run. 

OroMffe. — Pour one ounce of dislillod rinegar 
on a small quantity of hay saffron. When the 
color is extracted, poor it off clear — add gum 
water when used. 1'his color does not keep bril- 
liant more than ten days in its liquid state, there- 
fore make only a lilile nl a time. 

GoUUn Yellow. — Turmeric root one ounce, gam- 
boge one drachm, rectified spirits of wine, one 
and a half oanco---dige8t in a warm situation for 
three or four days, then strain it. 

Le<tf »/tow.'-Frtnchbcrric8 bruised one oz., 
water three ounces — boil over a slow ftrc, until 
reduced to one ounce nnd a half. A few minulca 
before it is removed from (he ilre, add one drachm 
of finely powdered alum. Whcu cold, ■train 
and bottle it. 

ScaHtt,—}A\x as much of the orange color with 
the pijik Baucct as may be necessary to produce a 
rich scarlet. 

RoiK may be made to any shade by adding more 
or le«B lemon juice with the pink saucer, — a di- 
luted solutiuu of citric acid in water will answer 
the same purpose. 

CriiM&ft, — Lny n coat of pink saucer, very deep 
on your iutcniJcd <:rinicion ilowen, and aflorwartu 
a coat of camiino. 

Carmine Liguid. — Carmine ten grains— liquid 
ammonia ten drojis— distilled water one ounce,— 
shake frequently, it is fit for us€ in 'M) minutes. 

Dark Ptirple. — Liquid archiU half an ounce- 
twenty drops Mturatod loluUtff of pearlaab, and 




9G 



MAGAZINE OK SCIENCE. 



five ^rrftiiii uf powdcrcj xhim — shake the in- 
gredients wifll lu^otlier ill a bcttle. 

lAffht Purple. — Decoclum uf lo^woud half au 
ounce— powuured iiluiii fi\ogrniiis — mixed. 

Lilac. — Same its purple, but made much tighter 
with gum wntcr. 

Brotcn. — Vory the tinta by adding either bUck. 
carmine, oninjcc, or Ipaf yellow. An infiuioD of 
Spanish liquorico, or tobacco* makes an eiceltctit 
brown. 

Drab. — Mix a araall quantity of Indian iiiV, 
TPith leaf y*lIow, 

Grey. — Indian ink and blur, diluted with gum 
water. 

Black. — Indian ink. 

Grvtn. — Vary the tinUof groen by adding blue 
or leaf yellow, qa required. 

Sap Green. — Csed in its raw Btatc. 

I'erdigria Cr«».— French Terdigria one ounce 
— dislilied vinccar, four ounces — boil for a few 
minutes orcr a alow fire, then udd one drachm of 
orcnm of tartar — when cold filter and bottle for'use. 

B'ue.— Prussian bine powdered, one drachm — 
oxalic ncid, one drachm— distilled watvr eight 
uuncea— it is incompatible with the otlier colors, 
but it forms a boautiAil ink or stainor, irithout any 
color. 



SINGULAR APPLICATION OF HEAT. 

SoMB years ago it wss observed, at the Comer- 
votoire dft ArU et Mftiem at Paris, that the two 
side-walls of a gallery were receding from each 
other, being pressed outwards by tbc weight of the 
roof and floors. Several holes were made in each 
•f the walls, opposite to one another, and at equal 
distances, through which strong iron bars were 
introduced, so as to traverse the chamber. Their 
•ends outside of the wall were famished with thick 
iron discs, 6rmly screwed on. Tliese were sufficient 
to retain the walls iu their actual poaitioo. But to 
bring them nearer together would have surpassed 
every effort of human etrength. All the alternate 
bars of the seriea were now heated at once by 
lamps, in consequence of which they were elon- 
gated. The exterior discs being thus freed from 
contact of the walls, permitted them to be advnnred 
farther, on the screwed ends of ^e bars. On re- 
moving the lamps, tlie bars cooled, contracted, and 
drew in the opposite walls. The other bars became 
in consequence loose at th«r extremities, and per- 
mitted their end plates to be further screwed on. 
The Arst series of bars being again heated, the 
above proceis was repeated in each of ita steps. 
By a succession of these experiments they restored 
the walls to tlie perpendicular position ; and could 
easily have reversed their curvature inwards, if they 
had chosen, llie jtallery still exists, with its bars, 
to attest the ingenuity of its prcsencr, M. Molard. 

MISCELLANIES. 

Sieam Dtrileri. — A gold medal was recently 
decreed lo the elder M. (.'haussenoL, by the Society 
for the encoaragf^ment uf Naliimal ludusti*)', for 
an apparatus lo render the cxpli»ion of slcam- 
boikrs Impossible. His inventinn is uiid to be 
perfect, both an rc^rds iU impruvomeuts on the 
safety-valve, and an ingenious conlrivanee to k^'c 
due notice nf danger lo the crew : while in the 
event of all the warnings of the macliiiicry failing, 
or being di.srei?arde<I, llie steam flows back upon 
ihe furnace, imd instantly cxtiiiguisbcs tlie ijre. 



flrrrF«*«;ir.— Anexbibilionf*"""T-"'v invented 
fij*c escape took place a ft'W d;i lir ioiuu' 

>ard of Uic workhouse *tf St. J - '' imin*lei; 

in thii presence of a nuiuberol the cliufdiwardeAS 
and orcrseers nf the varin(i«raetro|Kitt(an parishos, 
and other i;cnllemen. The »■ scujw in question ia 
the invention of Mr. Hawkins, «f Vii;o StrreU 
Rciiteiit Street, t asbier l« the ("ounly Fire Offic«^ 
and is certainly tlie ramt ^inipb' we have yet wit- 
nesse<L, its iwrtability being greatly in Its favor. 
tt t (insisis of three nq es, each 60 feet long, whieh 
may easily be carried by the pnlice, the weight 
bcion- iinly eight (Mrunds aii<l a hulf; and on Ibe 
otcurrenet nf a fire, one of thcH' ropes beinf; taken 
to an u|>-i>lair* window of the huuw on each side 
of timt on fire, and the end. at which is a vfrinK 
joint, thrown into the street — both can be joined 
with tlic third left below. An elastic belt nr«i 
also adde<l to (he screws, which sercral per»ma 
)>ajaing under their arms ilesccnded fruin the win- 
dows nf the secnnd flotH", n ilh the greatest e4M 
and safety -//iriT having been brought down in tha 
st}ace of tKC mintittM. A basket, or open bos, for 
the rescue of females orihildren, can alrabeat* 
tached to it, and their descenleflected with pcrlect 
«ifety. The exhibition appeared to eive the 
highest satisfacljoD to all wHa wiliiCKsrd it, and 
the cliurcbwardeiis of St. James' iujmediately 
directed Mr. Hawkins to leave one (or the u«i of 
thai establishment. 

Porcelain Lettert. — Those ar« intended to so- 
{lersede tlie ordinary wooden letters fised upon 
the facia of shop-windows, kc. Tbey are of eicxr 
color, and the gulden nuesare particularly beaDtiAil. 
Tliey arc cleansed most easily with a sponge, aod 
will shortly arrive from the manufactory tft 
SUffordshirc. 

To make Gold Shelh, or Liquid Gold for Primt- 
ing. — Grind on a 5ilab leaf gold with stiff gum 
water, or honey, very fine, aadiiig as you proceed 
moreof the gum water or honey, as yon deem nrees- 
sary. When the gold is redaoed to an impalpable 
powder wash It in a hrj^ muscle shell, with rain 
or distilled water, then temper it with a little of 
the chloride of mercury ; fix it to llie shell with a 
solution nf gum arahic in nhich husbeeu dissolved 
a HQiall bit of lump sugar. Spread the gold 
evenly over the surface of the shell and dry It— 
when used, it is with plain water only. 

The process for liquid silver is the samcas the 
abuve— only observe in uMng, temper it with the 
white of eggs instead of water. 



CORRESPONDENTS. 

M. B.— It U iropo*«iblt Mint ■ numb«'r "f tmiT^wtfin* «m 

IdkMi FrocD an on^ritvctl print, with . ' 

•ndeal Ihsl it ll)« tnk can l>c niaO' 

remorxl uf apart to Jinclher i'»pp( " 
J S. (Bo»"r )— \\V rill nol umicriiau'l vMiai Illl^ jfini.ni 

mcuii by <lnirtla([. 



Vol. i. price 6«. » »oie ready. — Alto tkt Second 
Edition qf A'wr. 1 fo 8. 



Communlrslian*. Book* fot Urtiow. iDveiiUoiu for lllw- 
trnthui. he, tu t>r adilrvuci) lo Ibe I^dttor, 56. GrvaS 
PrcMCil Sued. Ui llip I'rliilei; ot lo Iho Publubar All 
Lvtlcrn tniut be poil putt. 



PilnteC liy O. KsAitct.. «. WhU? llor»« l-M«. Mil* End ttoaA. 

rutiilthcd rvFry SBlunlny Iry W BBirtAiK. II. PiktcnnSM 
Row. Olid m»y be bad oi all BooluallaTS ajul " ^ 

Tuivu auii Couutxr- 



THE 



MAGAZINE OF SCIENCE, 

^nH Sf&ool of ^rts. 



No. LXV.] 



SATURDAY. JUNE 27, 1840. 



[Pbick IK 




V\\\\\\\ \\\\\\\\\\\\^l 



ti^ 





GALVANIC APPARATUS,— BATTERIES. 



(Remmtd from page 7* J 

t paper on tliia cabject considered the simple 

oil liu, without a rcfeFence to any cuutinued 

of sneh art^^ and ftlthongh we hare dt^scriboil , 

pspera introduced in formtr pnrtii uf 

the tffccK and BppUcatiou of fiucli 



iimple ekmenta in producing certtin svpriiiog 
effects, (ihc electro-type for exunpLe,) yet it is in the 
repetition of thete causes, and the oocomulation of 
these galvuik circles, forming what is called a ^- 
vanic battery, that enable us to wttrirss this wonderful 
scifince in it« full po«er(, and to jud^uf its mifbtx 
influence over aoimste and tnoniinate nature. 



VOb. U.^-KO. Xtll. 



98 



MAGAZINE OF SCIENCE. 



The fiillnwing is s pliun tIt:»crij)tion of some gal- 
ratic hfttteric^ in the order in which they were 
invented. 

The tirst of these is callnl the Voltaic Pile ( Pig. L) 
which name equally expresses the name of the iuvvtilur 
«nd thr fthnjic of the instrument. M. Volta n*ta- 
rally <x>ttclu(l<xl that if one jmir of platei prodnoed 
a certain effect, twu pair wduIiI prodiuse a greater 
degree of force, uud ho on. To confirm tbeflUpi>o- 
sition he procured some piece* of zinc, and wjine of 
ailTcr, each a* big as penny piecen, and bIko some 
pieces of flannel eomewhut smaller ; these he piled 
up, first putting a piece of ailvt^r, tluMi a piece of 
lioc. th*'n a piece of tlaimel, wetted with water; 
again silver, zinc, flannel, and 6o on in regular order 
till some cooiiiderabli) number wan piled up — having 
■ wire at the top and another at the botlum of thia 
pile, sud pafifiiug the wires through the Umba of a 
frpg, B» in tlic simple Mitcriinctits, hv. found the 
maaolea infinitely more acted upon than by a simple 
pair of plates. Also he found that when a pile of 
40 or hO fum had lM*en made, thtit if. he wettrd a 
£nger of each hand and held the wire himself, he 
felt a slight shuck in the fiiigerM, thus establishing 
the first grand and important fuct as to accumulatiug 
the fluid. Subsequeot experiments showed that 
when the flannel was soaked in fialt and water, 
instead of water only, the effect was stronger — and 
still more 00 when a dilated acid was a»ed. 

During all the period of arranging the pile, gal- 
vanic action is going on, the surface of the metala 
becoming tamiahed, and the acid becoming ex- 
pended. Thus the pile has many inconveniences, 
bestdea the trouble of building it up — hence the 
Bubetitution of other contrivances, llie first sug- 
gested was the Coronne df Toxseti, as represented in 
Figs, 2 and 3. Fig. 2 representing u aide view of 
a aerioi, holding a dilute acid, and containing each 
of them on the one side a slip of »uc and a piece 
of copper, so tlmt the line of one cell is soldered 
to the copper of the next, and that in every cup the 
Uquid divides the metals. Fig. 3 shows the section 
and general orraugcment of these cups seen end- 
wise. Thia was, like the former, tho invention 
of M. Volttt. 

l*he next great improvement was that of the 
Trough B^tery, inrente<l by Mr. Cruikshauks. It 
consists of a btfuart; box, t'orined of baV^ wood, 
and having a number of groovea cot in tho sides 
and bottom, about half through the wood. 

In these groarcs arc fitted donble mctalhr ((latent, 
formed of equal-sized pieces of xinc and copper sul- 
dereil togetlier at the top, and ju!>l large enough to 
slide into the grooves made to receive them, and t&ll 
enough to reach toobont an inch from the top of 
the box. They arc foittfiied in with common elec- 
trical cement, made of rosin, bees' -wax, (one-fonrth 
part,) and red ochre, in the following manner: — 
Make the box and plat/-jt quite hot, and have the 
box empty, and the plate-s near at hand. Then pour 
into the bottom of tho box some of the cement, ao 
aa to cover it a quarter of an inch deep, and imme- 
diately afterwords put in ns fast as possible, that is, 
wbijp the whole remaina hot, the platon, one in each 
giroovc, and be careful to press tltem to the bottom 
of the box. This being done, let the wbolc remain 
tiU so cold that the wax at the bottom is sot— ^then 
lay the box on its side, have a little sHp of wood 
to extend from end to end, so that the cement 
poured in shall run down between the various 
plates, and not be ifpilled by runuinif out. Pour in 
a sufficient quantity of the cement and let it get 



cold, then taming the trough over fill up td 
side in a similar manner, the trough will 
plete, and the plates all fastened. 

The plates are tuually put half an inch or moiv 
apart, but thia occaaions great loss of power ; thsy 
should be as dose as possible together, not mereijr 
for the above reason but because the trough is thm 
more ])ortable and requires leu acid to fill it. Sal* 
phuric acid and water is usually employed whtn 
troughs are made uae of. They are conveoirot to 
practice, but hable to be injured by the warping of 
the wood, and the breaking of the cement — thii 
Impairing the insulation of the ceUs. 

Deferring till the next papcjr the dc«criptios and 
comparison of more modern ftrrangementa, we will 
notice two batteries invented by L<: Broame . for the 
purposes of medical galvanism. Ndther • 
however, ever obtained any celebrity, nur < 
be oousidered any longer of utility for any p m , 
aa the excellent coil apparatus of Mr. BacM viTmc' 
has superseded every previous instrument fur locih- 
col galvanic uses. 

Figure 5 represents a mahogany box, wl:h the 
upper half formed like alid. In this box : . 1 

a series of round double* plates, fixed on ai j 

the box is furnished with divisions of glass, and tiiv 
plates turn round, a pair in each cell — thua thtt 
galvanic power ia generated. It is conveyed by a 
wire ^m each end of the battery as in other in* 
stances — to the patient or object which ia to ha 
galvanized. 

Fig. 6 is an extensive series of metaltir doubleplnlcs 
OS before, not strong upon a cord. Tliey arc when 
in use, Buspcnded 00 two supports projecting above 
the eu<U of a long plain box — when to be used, tlia 
box is filled with diluto acid and water, and iJm 
plates are to be let down into it, when the galvaniri 
action ensues, or rather is said to enxuc, for as thera 
are no divisions in the box to insulate each paiti* 
cular pair of plates, the action of the whole is 
problematical. 

{To be eontuwed.J 



ON MADDER AS A DYE DRUG. 

Maddka, a substance very extensively employed la 
dyeing, is the root nf the rubia tinctorum, placed 
by Linne in his class and order tetrandria mo- 
nugynia ; and by Jussieu, in bis family rubiaceCy 
named from thia plant. 

Although madder will grow both in a atifT claypy 
soil and in Baod,-it succeeds better in a m^^ 
rich, soft, and somewhat sandy soil ; it is 1 > 
in many of the provinces of France, in .\i- 1«.^, 
Normandy, and Provence ; the best Europ^-itn 
gruwth is tltat which comes from Zealand. Although 
often attempted to he grown in England, its cultirB- 
tion has not succeeded here. 

The best roots are about the thickness of a 
quill, or at most of the little finger: they are 
transparent, and of a reddish color, with a Stniaf 
smell ; the bark is smooth. 

liellot ascribes the superiority of thr madder 
which com» from the Levant to the circumstonoc 
of ita being dried in thr open air. 

The red coloring matter of madder may be dis- 
solved in alcohol^ and on evaporation a residuna 
of a deep i«d is left. Fixed alkali forma in tUi 



MAGAZINE OF SCIENCE. 



d9 



ft Tfetet, tba ralphoric acid a faira-colored. 
wA tiiv vnlphale of potash a har red precipitate. 
Vrertpttat«s of rvrioos shades may be ubtained by 
llttai* nitre, chalk, nfor of lead, and the tnuriate 
if Irnti. 

IW quantity of ozy-muriatic acid required to 
Iflrtroj the color of a decucUou uf madder, is 
dbmble what b nnaaaary to destroy that of a de- 
iSdtua of an equal weight of Braxil wood. 

Wotil would receive from madder oalyn [lerifihable 
4ye, if the coloring parCiclea were not fixed by a 
laae which occafioiu them to combine with the 
Hair mort^ intimately, and which in some mewnire 
4cftBitii them from the dcstrnctive influence of the 
4Br. For this purpose, the woollen stuffs arc first 
XaOed for two or three hoani with alum and tartar ; 
*Acr nliii^h ihey are left to drain: they are then 
thjirtfr irmng, put into a linen bag, and carried 
h ' ''e, where they are suffered to remaio 

L 

1 i.c i^ti^iinty of alum and tartar, a.«» well ok (heir 
pr«purtiua<, vary much In different manufuc tones. 
BlUot recommends five ounce* of alum and one 
of tartar to carh ponnd of wool. If the 
rtloa of tartar be increased to a certain degree, 
of a r«d ft deep and durable cinnamon color 
tlpra^ared; because, as we have seen, acids have 
• teBdeDoyto give a yellow tinge to the coloring 
flTOrJea of madder. Berthollet found that by 
mployti^ one-half tartar the color aenittbly bordered 
■Mre oo the cinnamon than when the proportion 
«M oraly one-fourth of the alum. 

In dyeing with madder, the bath must not be 
yWitiittiKl to boil, hecnusc that degree of beat would 
the £iwn-colored particlca, which nre less 
than the red. and the color would be different 
AOH that which we wish to obtain. 

Tbt quantity of madder which Mr. Poemer em- 
"'-'-* •' noly one-third of the weight of the wool ; 
£§tt adnaes only one-fourth, 
•ul be boiled for two hours with one-fourth 
^ mpperoaf i. e., green vitriol, then washed, and 
ifterwarda put into cold water, with one-fourth of 
madder, and theu boiled for an hour, a coffee color 
ll froductd. Bergman adds, that If the wool has 
Ml been aoaked, and if it be dyed with one part of 
mnuru and two of madder, the brown obtained 
krwnt^rt nnnn n red. 

-m ploys a solution of tin in Tarions 
. ihc preparation and in the maddcring 
J doth. He used different solutions uf tin and 
boikd that the tint waa always more yellnw or 
fasik-oolored. though sometimes brighter than that 
vblitaied by the roinmon process. 

Mr. Oubliclie dnctibes a process for dyeii^ Bilk 
witfk madder : — For each pound of ailk, he orders a 
bath of four ounces of alum and one onnce of a 
lohition of tin ; the H^juor is to be left to settle, 
«V^ ft T!< tn be decanted, and the silk carefully 
'td left for twelve hour*; and after 
jti, it is to be immersed in a bath 
ummg imif a pound of madder, softened by 
with nn infuMoii of galU in white wine ; 
tb ii to be kept moderately hot for an hour, 
dicr which it u tn bf made to boil for two minutes. 
1i%'h«A taken from the bath, the silk is to be washed 
teavtrammuf water, and dried in Uie sun. Mr. 
Srfdadie compares the color then obtained, whir-h 
li MTf permanent, to the Turkey red. If the g&lLs 
kt JiA oak the color is dearer. A great degree of 
Iri^^Ltaea* may be rommunicaled to the Arst* of 
tbosr ^ aftervsfds paaaog it through a tnith of 






Braxil wood, to which one onnce of solution of tin 
has been added ; the color thus obtained, he caya, 
is very beautiful and durable, 

Tlie madder red uf cotton is diatingui<li<sd into 
t^'o kinds; one is called simple ramlder red; the 
other, which i« much brighter, is called Turkey or 
Adriiiuople red, because it comes from the I^ewnt* 
and has seldom been eqoaUed in brightneas and 
durability by oar artists. 

Galls or sumach dispose thread and cotton to 
receirc the madder color ; and tltc proper prepara- 
tive is acetate of almnine. The nitrate and manate 
of iron, as preparatives, produce a better effrrt than 
the sulphate (green vitriol) and acetate of the same 
metal ; tbey both produce a beautiful and well 
saturated violet color. 



SPECIFIC GRAVITY 

U Uic rGlativc, compaiutlve, or apparent gravity ia 
ojiy body, in respftcl to that of on cq\iiil bulk or 
magnitudo of another body ; denoting thai gravity, 
or weight, which ia pecoliar to each species or kind 
of body. 

In Ihia sense, a body Is said to be apccifically 
heavier than another, when under the gome btilk 
it contains a g/caler weight than the other ; and re- 
ciprocully the lattiu' is said to be spcctfieally lighter 
tliau the furiner. Thus, if llicrc arc two equal 
spheres, oiu'li one foot in diameter; the one of 
lead, and the other of wood : since the leaden une 
is lound heavier Uian the wooden one, it iasaid to 
be spccidcally heavier ; oud the wooden one speci- 
ticftlly lighter. 

Tliis kind of gravity is by Mine colled relative ; 
in opposition to absolute gravity, which increases 
in proportion to tlie quantity^ or mass, of the body. 

I'or gases, common air Is the ituiudard ; Uiuii air 
ifl «aid to be 1.0000. and any deviation of grnviiy 
In other gases, is noted accordingly: thus hydrogen 
gas is 0.0732. Water is the standard fur liquids 
and solids; it is also Htatcd to be l.OfJU. but un a 
different scale. Sulphuric acid in comparison with 
it, varies in gravity, from 1.7U0 to LlKKJ. 

A body specifically heavier than a fluid, loses aa 
much of its weight when immersed in it, as i« 
equal tn the weight or a quantity of the fluid of the 
same bidk nr magnitude. Hence, since thespociflc 
gravities are ns thn absolute gravities under the 
same bulk; ihc specific gravity of tlic fluid, wilt 
be to that of the body immersed, aa Ihu part of 
the weight lest by the solid, is to the whole wcighL 
And hence the specific gravities of fluids arc as 
Lhc weights lost by the same solid immersed in 
them. 

As bodies spcciflcally heavier than water, when 
immersed tltercia, lose of tlieir nbsoluie weight 
taken inihe nir, what an equal quantity of water 
ill air would actually weigh; consequently^ the 
tiijfferencf o/ the tueu/ht n/ any tuck hudy, taken 
first in air, and afitrr-warda in water, wilt o/ways 
be the Just wetght qf a t/uanttty of water, equai in 
hulk and dimensions to those »/ the body under con- 
sideration: and will be at aU times /airly compa^ 
rabte vith it. 

'I'his famous proposition was first discovered by 
Archimedes, on the following occasion. Hiero, 
King of Sicily, ordered his goldsmith a certain 
quantity of gold to make tho crown royul. It was 
indeed well designed and finely ombclli&hcd ; but 
the artist it seems had made Crvc with some of his 
Majesty's gold, iiud hud substituted iu its room an 



= ?uy. 



100 



MAGAZINE OF SCIENCE. 



cqumJ quantity of lilTcr, or copper. Oa doUvory 
of the woik, A raspicion of tnal-practke arofle; 
tbo ceo wn wu ordered to be surveyed, and the 
Tcferred (o Arcfatmedu, witA uMtnictiona 
00 niemxiB to de&ce the workmanship. It Uy 
^long before this roathematiciftn, and the maker 
lu^bk lumeelf pretty Bcctire of hw payment, ll 
tppeaed, however, one day, as the philosopher 
ras itepping into a bath, tliat ho took notice thai 
^fbe water row in the both in proportion to the part 
of hia body immersed. From this accidental ob- 
•erratjoD he received a hint, wherewith he was so 
Irinsported, that, he jumped out of the bath, and 
nn, naked, about the streets of Syr«cuso, crying 
in s wild manner, J have found it i J hate fovmd 
it! 

In consequence of this speculation, he made two 
massj^s of the same freight as the crown ; one of 

Sold, the other of silver. These he severally let 
own carefully into a vessel of water, wherein the 
liae of the Raid might easily bo determined by 
BBsosare. Being of diiTerent specific gravities, 
iVber were, consequently, of diff^erout ma^itudcs, 
and, on immenion look up the room of dilTcrcnt 
qimnhtit-f orvraler; by cumparing these effects 
wiUi their absolute gravities in the air. Xiv became 
faHy mister of tlie relation in point of weight, 
which each of thew roelsis had to ^ater. and con- 
■eqncntly to each other. Ho then examined the 
crown iu the same manner; nnd by comparing tiis 
cbsorvations, he at length, detrcud the cheat, and 
1 iccurat«ly ascertained the quaDiitiea of gold and 
Silver which it contained. 

Rulea. — To determiite tht tpeaficgravity nj tolkh. 
— Fill a phial with water, and marie the wt^isht of 
the whole accurately, in yraina. Now weign luO 
crainii of the nubstancL- to be examined, and dmp 
it gTfidually into the wuicr, in the phial. The dii- 
fi-rrnt e in weijiht, of the buitlo with itJi contents 
•j,..« ""I .»,..■ it was filled only witli water, will 
• ' citic gravity i-f the substance 

! ' Q. For example, if the bottle 
|Weighii 4U griuns more than it did when it was 
~ id with water only, it shows that 100 groins of 
mineral displace only GO grains of water ; and. 
incntly, that it is of nearly twice the specific 
ly of water. 
Toftnd the BpteHfic gravity (/ a /fuut. — On one 
arm of a balance suspend a glubo uf lead by a fine 
' reail; Ami to the otlier fasten an equal weight, 
Iwhich muy just baliiitc it iu the opon air. Im- 
ihc glob'.' in \)\v lluid, and observe what 
Vright bnlonccA ii ihrn, and consequently what 
voil^t is lost, which [^ pmpurtional to thr specific 
pavitT M above. Aii'l t:uii. the proportion v( tho 
ffpMtJu gravity of uuc lluid to onutiier is deter- 
mined by iminursiii}:; tiiu globe Rucn-jnively in all 
lhi< flniila, and ubflcrving thr wci^ht<i loiL in r-Arh, 



■ ' 


-.er'»frf.— 


m 


tj much 
i»d moss 
^irr Kodv 


^^^bad vui 

K 

^P Theu. Af 
H Is to the ' 


.^ r.er 
■ m 

^- .....: ... ~-.*. *i jta 

tract the lesa of thcae ro- 

' r 

■'i.T 

I tM*dy in air, 



^ tatlM t^Kt tuc ^nviiy ol thi; fluid 
To ih» •pvGifte fnniy of thai body. 



The CoUowiag tahlo exhi^Ua iho 
of a groat number of dUSarsM foU 



r^ 



SOUDB. 



riatinuiB si.iro 

Gi>ld IS.WO 

Irtdion IS,«S0 

Tunfitra 17.400 

Moroury IXSOO 

Pallulium II4O0 

WocUnum 11,470 

LMd II.UO 

lUiodluB 10,4M 

SiW»r 10,00 

Ulinitfth 9M0 

Uruunin .......... S.iOO 

Coppv MM 

CubaU •.CM 

Molybdeauai a.Sao 

Niclut a,«M 

Ancnu! 9.190 

Hangkii*** ft.000 

Irrm r.TOO 

Tia rjOO 

Tim- «,Ma 

Antlmoay ..,.,^..., S.TOO 

TeUnnam C^ISO 

Cliriiiuium ijttKi 

Coluinbium &.S00 

S«l«auiin , -MOB 

Ruby.OrlciitaJ 4J09 

Gwntt, JbitMulaB . . <1M 

Banuni 4.0(10 

Slnintlum }jwe 

Diamond l,aiT 

Watu-tekd 1,110 

M»rbl xm 

Cornl 1.700 

Uavvt I.MO 

Rwck ctyical S.CM 

WmI t.«M 

r,la*j t.soo 

i^itni i.sro 

Onyx •ton* UIO 

GlaulMrffkll |,1W 

Oyitoralwlli IfOB 



Vimd 



CmI. 



lUvwv- 



W«lMS*tt«t 



ri47iiM. 



QoiekaUvn 14.000 

UU of vIMol IJOS 

on or uiur I.AM 

Itonry I.4J0 

Hydroehlunc kcid .. 1,91} 

Nitncacitl |JH)0 

Trvult IJM 

A«{u>rwU 1.3)4 

lliiraut4eo4 1.1«« 

llnM i.au 

Co«'» imUk |,UU 

&»• watoT t.gae 

S»nuBorb4URaab]«<i4 I.OM 



oa«t 

Sptna< 
MfllaC 



Vapow Bf irydnodls *tkm „ . „^, 

!7r-.:::;: 

.^iTiM .... 

\ ■■ ■■ ■ - ^-^-iMmwiM MrtM*M 

* '■ I'i-tna ¥lhmi ....,•.••. 11 

»;.> ...'IU.- xff« 

I'lHu-Uwrlv gM UNO 

Vmiar or mBrlallp sdiBr mJtM 

Bwotennu Mi4 laa .. t.ttB 

t^MfMi , .•», ijmti 

Va|N.iiror n ^ ai O tm Awaoat I 09 

Nilrutta o«UW . IJBM 

CAfOoBtetcUl Mli^J 

Morudc sctd CM ^^^H 

OKyg«fi(M JB^B 

VUliwmam IJIW™ 

Oldbotgw .,.,..,.,... O^lM 

AM»tm, m l Um — gat •• ,. COM 

llydr<»-«rM*tv^M\*"".'r.'!."».'.*i ft*«« 

Vimmidwmm " B2tl 

Iwiliwlgo osam 

C i rt w Htt i Oj i n y ,.,., •->»)■ 

AN#iii«l*d bjAr^ifM , 
ll;4nifcs|M 




MAGAZINE OF SCIENCE. 



101 



tt 



Tlw ■pectfie gnritifs u( the bndies mntAined in 
t%f! fort^ing xabXCf and in all tables of this kind, 
he cotuidered as the mean of a nambcr of 
iits madr on each, nnd therefore cannot be 
eofifiidered as ptrfectlj agreeing with the reaolt of 
• ilbigi« experiment, made for the jiorpose of deter- 
vdzung the B]>ecilie gnrity of any particular sub- 
itawe : becaote the parity, the temperature, and 
■m a l other caaie«, materially atfect (he reault of 
•a ctperiment of thiii kind. 
Thrw nuubere being the weight of a cubic foot, 
* eobic inches, of each of the bodies, in 
IQis oonceB ; by proportion, the quality in 
iQv Miner weight, or the weight of any other quan- 
tity, may be rcndily knotrn. 

f..r ^i^L.r.lf., Required the content of an ir- 

uf tnilUtone, which weiglu 1 cwt. or 

.foaaora. Here, as 2500: 1792:: 

t 'iZiy^ cnbic Inches the content. 

.. — To tind the weight of a block of granite, 

tbsue length is A3 feet, and breadth and thickneaa, 

tmk 13 fi»t ; being due dlmoonoas of one nf the 

of granite in the walls of Dalbcc. Here 

12 N 12 = 9072 fe«t is the cuotout of the 

- therefore as 1 : 9072: :3500 to 31762000 

K5 tons, 18 cwt. the weight of the atone. 

-'iitrtain the purity of tin, &c, pcwtercni, and 

dcvlere in tin, cast a bullet of pare tin, and 

of the mixture of tin and lead, wbicli they 

examine, in the same raoold ; and the more 

b«Det of the iniztore exceeds the ballet of pura 

sreight, the more lead they conclude it con* 



MAKING SHAGREEN. 

Ikis manafacture is one of those in which the 
and west of Europe are dcAcicnt ; Bhagrccn 
imleed but little used, an imitation of it in 
fMtr vulficing for the f^nerality of the osea to 
^noh H WB9 formerly B]>plied. 

shagreen is a species of leather, munuAu;- 
Uron the skins of horses, mules, or asses; 
particularly from the croup. The Orientals 
>lhc9e skins for some days to the air and sun ; 
liter which they ton them, and reader them ts thin 
poaaible. Mustard seed is then said to be placed 
the skin in rrgnlar order, the skin put into a 
I, and dried. The impression of the seed re- 
rwnaina on the skin, and, when properly prepared, 
Iha ahagreen is beautiful; but if by any accident 
tile tnpression la defective, the skin loses much of 
its nine. 

fifaagreen grows so very hard, as it dries, that the 
I^^TT*" case-makers ore obliged to soak it tn water 
tQ nsoder it fit for their use. 

I^ appearance of shagreen may be easily Imita- 
bed Id Morocco leather ; but this imitation is eaaily 
AstxngnJahed from the real shagreen. Shagrcency 
Uoroeoo leather is torn with ease ; real shagreen is 
that it cannot be torn by any ordinary 




KaI thagreen maf be had of any color, but the 
Ipty ahi^rrvti, manu&ctured at Constantinople, is 
Iki »oat highly esteemed, both for its beauty and 
WMilglll It also Is to be found of a black, green, or 
•Ute color, and red, which Isst is the dearest, on 
iBBOBOtof the cochineal used in dyeing it. 

flka Tttfka of Constantinople have the rcputatioo 
of bd^g t^ beat manufacturers of shagreen : then 



thiMe of Tonis, Algiers, and Tripoli. That msnu- 
ftuitared in PoUod is very harsh and nerer well 
colored. 

Sham shagreen is made by the Western Europeana 
from aheep and goat akins, wliich are first tanned, 
and then ahagieened, by beln? passed through a 
rolling press, theroUen of which arc engfnTcd, and 
heated as much aa may be, yet so as not to render 
the skin homy. The appearance of shagreen is 
perfect, but the toughness of the real is wonted, and 
thin imitation is easily torn. 

Ijitely a Mr. Merim^-e, in Prance, has attempted 
to improve the toughness of the aham ahagreen, by 
the use of the acid of wood, but with what lucoeaa ia 
not yet known. 



To the Editor qf the MagAzinf qf Science. 
Sir — The following is a description of a Filtering 
Machine which 1 have oo»stra<;ted, and liave had 
in use a considerable time, and strongly recommend 
it tn all who wish to obtain pure water, it being 
extremely simple an<L economical in its oonstructionf 
at the same time purifying tlie water, equal to any 
of the patent filter* now otTereil for sole to the 
poblic, and which many are prevented from udng 
on account of their expense. 




A represents a square or cyUndrical vessel made 
of any suitable material; the one 1 have constructed 
is of zinc, which is cheap and durable. B a par- 
tition fixed so as to divide the vessel A into two 
chambers C and D ; the botttom of this partition 
must be bored full of holes, or made about ono 
inch shorter than the vessel A, so as to allow a 
free passage for the water between the two cham- 
bers. £ is a cock to draw off the filtered water in 
the resevoir D. Procure some sea or river saud, 
and after having ire// washed it, fill both the chara- 
bens C D with the same, to the height of five or dz 
inches* After having done this, fill the chamber C 
with good charcoal powder, to the depth of two or 
three inches ■ -the nmcluuc is then ready for use. 
Pour the water tn bo hltert^d into the rhnniticr C, and 
it will descend gradually through che cluircoal and 
sand, and ascend through the sand in Uie duui^bcr U 
beautifully clear and pure. 

Particular care must be taken to thorongkiy 
cUame the tatui, and have yooiftM//-6un>i/cAa''eoa/, 
which ought occasionally to be renewed. A lid 
should be fittcil to the top to ki«p out dust, tiC 
And it ie an improvemeat to paas tlu; water through 



MAGAZINE OK SCIENCE. 



« stTBiner, or eponi;e, pUerd ovrr the chamber C, 
this will prrreat the charcoal from becomins f""!* 
•U ftuon, from the (jroMcr impurities. My nppsratua 
which is only 12 inrhcfl tliBmeCcr, and IB deep, wilt 
filler about I gallon per hour, but of courw the 
rapidity 'yf filtering, and in proportion the purity of 
tite wAtt^r 6ttered depeudtt much upon th« dq»ih of 
the Btrala of sand and charcoal. 
TltuniU>u Lotlgc. ChcAiM'. S S, 



GOLD-LEAF 

UsifAtLY signifies fme pnUl beaten mlo plates of 
«i(cei^iD)i; Ltiiniie8&, which are well known in the 
arts ofpilding, &c. The prrparation of pold-leal*, 
according 10 L>r. Lewis, is as fallows: — " The 
gold is mellud in a black-lesd crucible, with fcjrac 
borax, in a wind.fumace» called by the workmen 
a v/ind'kate : aa s^un as it appears in ixTrTifct 
fuBion, it is poured out into an iron in^ot mould, 
6 01 8 inchos long, and J of on inch wide, pre- 
▼iously greoAcd, and UtiAlcd, 90 as to make the 
t&Uow run and smoke, but nut take llame. The 
bar of gold is made red-hot. to bum off the 
unctuous matter, and forgvd on an anvil into a 
long plutc, which is further extended, by being 
paaftcd repeatedly between polished atucl rollers, 
till it becomes a ribbon as thin ns paper. Formerly 
ihe whole of Oiis extension was procured by 
means of tiie hammer, and some of ihe Fn nch 
workmen arc still said to follow the same piaciicc : 
but iho ubu of the flattinF;<mill both abridges tho 
operation, and renders the plate of more unlfonn 
thickness. The ribbon is divided by compasses, 
and cut with scissors into equal pieces, which 
consequently arc of equal wcijthla -. these are 
forged on an anvil till they arc an inch square ; 
and aftcrwarda well ncaled, to correct the rigidity 
which the metal hna contracted in the hammering 
and flatting. Two ounces of gold, or 960 grains, 
the quantity which the workmen nsually melt nL 
a time, make 150 of these squares, whence each 
of them weigh six grains and two-tiAhfi ; and as 
*J02 fTRtris of gold make a cubic inch, tho thick- 
ness of ihc square plates is about the 70G part of 
an inch. 

" In order to the further extension of these 
pieces into Bnc leaves, it is necessary to interpose 
BOinc Knoolh body bclwcLMithom and the hammer, 
for Ro(\ening its blow, and defending them from 
the rudeness of its tulcnuedialu action, as also lo 
place between every two of the pieces some 
proper intermedium, which, while it prevents 
their uniting together, or injuring one another, 
may sulTcr them freely to extend. Both these 
cn<u are nnswort'd by certain animal membranes, 

" Tho gold-boaters aso three kinds of mem- 
branes ; for the outside cover, common parch- 
ment; for interlaying with the gold, flrrt the 
smoothest and closest vellum, made of calf-skin; 
and afWrward^ the much finer skins of ox-gut, 
fftript off from the largo straight gut slit upon, 
curiously prepared for this use, and hence called 
ffotd-bealer^ skin. The preparation of tl;e»c last 
is a distinct business, practised by only two or 
three persons in the kingdom, some of the par- 
ticularsof which have been already adverted to. 
The general process consists in applying one 
upon another, by the smooth sides, in a moist 
aiate, in which they readily cohere and luiito 
inseparably; sirctchnig them on a frame, nnd 
carefully scraping otT the fat and rough matter. 



so lu to leave only the fine exterior 
the put f beating ihem between dor, 
paper, to force out what um luusity may ici 
them, moistening them once or twice wiliii 
inlUMon of waxm apices ; and Uslly, drying 
jtressing them. It is said, that some cAlrll 
gypfluni. or plaster of Paris, is rubbed 
hare's foot both on the vellum and the ox« 
skins, which fllls up such minute holes 
happen in them, and prevents the gold-I 
sticking, as it would do to the simple 
membrauc. It is observable, that, notwii 
the Tast extent to which the gold is beaten I 
these skms, and the gront tenuity of 
themselves, yet they sustnir, continual rcp«t!l 
of the process fur several months, without 
tending ot growing thinner. Our work i 
that aHcr 70 or &U repetitions, tho akins,^ 
they contract no flaw, will no longer 
gold to extend between them ; but that 
ngnin be rendered fit for use by impi 
them with the virtue which they have 
that cvMi holes in ihem may be repaired hf 
dexterous application of fresh piece* of 
a microsftopjcftl examitmtiou of some akina 
had been long uncd plainly showed these 
Another method of restoring their virtue is 
interlaying them with leaves of paper niotsl 
with vinegar white-wine, beating them for a 
day. and afterwards rubbing them over as at 
«ith planter of I'arta. The gold is said Co 
between iliem more easily aftey they hare 
uHed a Utili; than when thry ace new. 

"The beating of the gold is performed oi 
smooth block of black marble, weighing from 
to GOO pounds, tlie heavier the belter ; about 
inches square on tlie upper surface, and sooiet 
less, lined into the middle of a woodeaj" 
about two feel square, so as that the surfa 
marble and tho £rame may fonn one 
plane. Throv of tlie sides arc fumisi 
high ledge -, and the front, which is ope 
leather strap fastened to it, which the gol 
takes before bim as an apron, fur preset 
fragments of gold that fall off. Three 
are employed, all of them with two nuind 
Bomoffhat convex faces, though commonly 
workman uses only one of tlie faces; the 
called the catch hammer^ is about four 
in diameter, and weighs 15 or IG pounds, 
sometimes 20, though few workmen con 
those uf this last »ize; the second, railed 
shodering hammer, weighs about 12 p<iunda, an< 
about the same diameter; the thud, called 
gold hammer or JituMking kammnr, weighs 10 ori 
pounds, and is nearly vi the same brLadth. 
FreiK'h use A hammers, differing both in sixe 
shape fVom those of our workmen ; i]iey have 
one face, being in figure truncated cone*. 
first has very little convexity, is near five tDcl 
in diameter, and weighs 14 or 15 pounds; 
second is more convex than the first, aboat 

inch narrower, and scarcely half ita weight ; 

third, still more convex, is only about 2 inches 
wide, and 4 or 5 pounds in weight ; the fourth or 
finishing hammer is nearly ns heavy as the first, 
but narrower by an inch, and the most convex «f 
all. As tliese hammers differ lo remarkably fi 
ours, it is thought proper to notice them, loi 
the workmen to judge what advantage one 
may have above the other. 

" .A hnndred and fifty of the pieces of the 
ftro interlaid with leaves of vellum 3 or <1 inrhf 
square, one vellum leaf being placed betw^tin 



MAGAZINE OF SCIENCE. 



103 



tn of the picc<>8, iind. about 20 more of the 
velfann losres nn uieuuisitles; uvu-rlht^bti is drawu 
*. ; ■ .il bulh ruUs, &i)U over 

k'ii ■ direiliuii, so that iho 

k> .... A cllnm leaves 19 kc-pt light 

•t .1 siilcfi. 'ihc whule is beaten with 

I'. !..tmmer, and cvury uow and then 

v.. >!uwn, till tiio gold is stjctohcd to 

i:. :|ie vcltum ; the case bet nir f rum time 

1- t fur diicovcriug how the extcnsiou 

p :io pjickct, at times, bciit and rolled, 

I- iwt^en llie h&ndfl, for proeuriug suf- 

II u to K^IU, ur, as the wurkmcn say, 

t. i^old work. The [iteccs taken out 

t . the velliun leaves, are cut iB4 with 

;. and the 600 divisions hence re- 

• '^Id in the same manner, with 

' skins 5 inches square. The 

: — . ..^..:i'.ed with a lighter hammer, till 

Ike coldou jilatea have again acquired the extent 

t/ihr skins, rhey are a second time diyided into 

4 ineol used for this division is a piece 

u: an edco. the leaves being now so 

nire of the air vr breath cou- 

•- knife. TIlcw loet divisiuns 

. .. , that the skius uceessary fur 

'wccn them would make the packet 

-. bouten at onco; tliey are parted 

nhich &rc beaten separately with 

iiiimmcr, (ill tliey are stretched for 

v,.r •■uifi i:;iiitothc siie of the skins; they arc 

Do« ftiund to be reduced tu the preatvut thinness 

• : . V »iU admit of, aiid indeed many uf Uiem 

his period break or fail. The French 

II. according to the minute detail of this 

^iv^-ci-i piven in the Encyclopedic, repeat the 

i)Tti4>-'ii and the beating one more; but as the 

• f gold. tAkcD for the first operation, hare 

lus the area of those used among us. the 

t' '"arcs from an equal mrca is the same 

>hi, vix., IG from a iquarv inch, {n 

itowcTor simple the proecss appears 

.iAMl deal uf address is requisite for ap- 

!ie hammers so as to extend the metnl 

ttmurnity from the middle to the sides ; one 

i a y my tr bluw i» apt not only to break the gold 

|^«Hc Kill I., eut iho skins. 

last beiifing, the leaves are taken up 

^7 i a cane iui>trumcnt, uid being blown 

l4l i^D b. LeaUier cushion, arc cut to a size, one by 

orcf ^ vi'.h a square frame of cane made of a proper 

with a frame of wond edf:e<l with 

.■:■ ihc-n fitted into books of 25 loaves 

; "f of whieh is well smoothed, and 

d-lwle to prevent their slicking to 

' ch, for sizing the leaves, use only 

, cutting ihcm first straight on one 

\\'iin irrto the book by the straight 

:'i:ig oU' the superfiiious ports 

I lie edgea uf the book. The 

. .L gold leaves is somewhat less 

•tquturo ; that of uuxb from 3 inches 

ihs. 

< ss uf gold beating is considerably 

ihc wcatJicr. In wet weather, the 

..cwhat damp, and in this state make 

1 of ibc guld more tedious: the 

xdio dry uid press them at every 

\ Hith care not to ovcr^dry theut, 

r ^nder them tinfit for furliicr service. 

complain more of frost, which ap- 

• t the metalline leaves themselves ; 

Si iTtiiT. a ciiid-leaf cannot easily be blown fla^* 

Inl bfMlcSk wrinkles, or roiu loecther. 



** Gold'Icaf ought to be prepared from the flnrst 
|Culd ; AA the ailmixlurc of other metals, thutigb 
in too small a proportion to scnbibly alTert the 
colur of the leaf, nould dispose it to the loa sof 
Its beauty in the air. And indeed there is liillo 
temptation tr> the workman to use any other; the 
great-er hordnesi of alloyed gold occasioning as 
much to bo lost in point of time and laboui and in 
the greater number of leaves tliat L>reak, as coii 
be p-itincd by any quantity of alloy that would not 
be ut oiicv discuverablc by the eye. All metals 
render gold hurdc-r and mure difiinill of extension: 
even silver, which in this respect seems to alter 
its quality leiis than any other rnetoj, produces 
with gold a mixture sensibly harder than either of 
them separately, and this hardness is io do art 
more felt than m the gold-benlers. 

'* The French arc said to prepare what is called 
the tjreen gold-leaf, from a composition of one part 
of copper and two uf silver with eighty of gold. 
bnt this is probably a mistake.- for such an admix- 
ture gives no greeuoess to gold : and 1 have been 
informed by our workmen, that this kind of loaf 
is made from the same fine gold as the highest 
gold>cnlored sort, the greenish hue being only a 
superficial tint induced upon the gold in some part 
of the process: this greenish leaf is little other- 
wise used than for tlie gilding of certain books. 

" But though ilic gold-beater cannot advan- 
tageously diminish the quantity of gold in the leaf 
by the admixture of any ntJier substance with the 
gold, yet means have been contrived, for some 
particular purposes, of saving the precious metnl. 
by producing a kind of leaf called ptwttf gold, 
wliooe basis is silver, and which has only a su- 
perficial coat of gold on one side : a thinner one 
of gold, laid Hat on one another, heated and pressed 
together and cohere 4 and being then beaten into 
fine Icares, us in the foregoing procces, the gold, 
(hough its quantity is only about one-fourth of 
that of tlie silver, continues every where to cover 
it, the extension of the former keeping pace with 
that of ibo lauer/' 



JAPANNING TUNBRIDOK-WARE. 

BY k rCKBIttlMSB-WAftE MAMDrACTUKEB. 

Stcccss in vorni&bing Tnnbridgc-ware boxes, &«., 
depends very much on the vaniisli euipluved — vie., 
white hard spirit, or Tunbridge.woic varnish; as, 
if this '\* not of tlie |>cculiar kind suitable, what- 
ever pains ymi may take, wit! be un.^uccessful : the 
white hard' vamifin uf the shops, though good for 
other piir]»o5cs, will not answer for this ; you may 
procure the rit;htkind at Smith's, 121, ForetStreet, 
Ciipplegate. It muKl ahvays be used in a room 
heated a few degfiMrs above summer heat If the 
rtxim is too cold, tlie varnish when laid on, will 
turn white— or, as it is technically termed, chill; 
and if Kk) hot. it will rise in small bladders or 
blisters. Botli these must be avoided. Use it in 
a pot witii a wire fastened across tbe lop, apuiist 
v^bich the Itwl, (a fUil camel-hair Tarni-.li irxil,) 
must be worked continually, to regulate the quan- 
tity in the tool at once ; the surplus running from 
the tool and wire ugain into the pot— it is nut so 
good fur keeping, and muiit be kept from tlie air 
OS much as possible : tbe highest rectified spirits 
of wine id the only tiling that will improve it if 
too thick, and soften the lotrl if it get^ quite hard. 
Tliis varnish I shall, in my future description, call 
spirit vamisb ; and 1 have been thus parCiculu-> 



MAGAZINE OF SCIENCE. 



4rnrQdi an the |iroprr qnnlitr and 



in spcftl 



It «{U he 






paintiiit; xui 
itie 



I'lv 



<ll pt iatiag. but in « dry stsle; they 
CrMM tttt0 tti turTkcntUH' ami let dry; 




mtwl, 

,' it 

iLf or 

t\tloni ttAo«l ue l)ic ftaine lu for 

are to be 

they ate 

, m*mr t>r llic smooth colors, u 

-hisc-k, &c., do not require grind- 

^••l" *ir»l. 'Hic coh^rs when used nrc 

•►•f ■ « palpttf, or marble *lab, rather 

J0£j»Ua tajhil varnish, and thinned for iiw with 

CvllwtLiu> ; they rcijuirc <:-o|>al varnish enough in 

■kUT UiPin bind and dry firm and work free, hut 

«»l rnnuich to make ihcm nhimnj; or !slicky. Witli 

tbwft comrs, \oa mav jiaint Krn*>P^ "f flowers, 

[■Ih'Uk, ivralK'soue burdcrs. ur imitations of wood, 

[AbQ.j when gilding in wisheil. »m japan gold nj* 

lyt bearing in miud, ibul any crround color, 

m wond, St.c.,y u|>on which ^Id oruail^nls 

Fto ap|irar, mast have one coat nf spirit varnish 

crar it bcfttre "iizin^; whicli is always necessary 

wliMi flowers, ^lc, are painted nn a black or 

color grutiud-^llie spirit Turniith preventing 

miul color from wnrkiug^ up. Colored prints 

iwingK on iKipcr, patted clow and tight on 

wood, form a preity centre ; thiy must alwaya 

Iw ttizcil with iungla.<iH size twice over before tliey 

»re tarni?thcd over with ihr spirit rarnish. Have 

A little cu]t of turpentine by you when i>aiutin^. 

to uiui!«l4'n ihf penciU (camel-hair) and make them 

wtuV free — wash them in turpentine, and keep 

your colorK from the air as much as p<issible. 

The articles arc usually mado of eitlier horse- 
cfaeanntor i^ycainure wikmI, Uic whiter the better, 
andahonldbc w'tll OnishedofT with glass paper; 
iivipe tbem and give them one coat of spirit 
varnish — thi.i raises the grain; rub down with 
Abb glass |>aper when dry ; wipe from tlie dust, 
and Tar^ifili again with jtpirit Tamiflh. and they are 
properly prcpareil for painting; but prints or 
drawings must be pat on preWous to thia prepara- 
tion. In preparing articles for ladies to i>aint on, 
«i they UM water colors instead of cojul colors, 
emit tile two coatfl of spirit vami!>h, using instea^l 
« white yamifih mode nf finely powdered 6ake 
vtute and isiuglafs .siae, used hot, rubbed down in 
tbe same way and repeated. 

The pntoecsof vamlshiiig and polishing, after 
lAinting, &c., I will describe in my next paper. 

IYour*», &c. 
UEtn. 




^ 



«^^J«^MV^n^Af 



MISCEIXANTES. 



Aiumer to Query 167. — Preparittion of TVriey'j 
Crtipitjor haliftoiu. — First take the crop and free it 
from the thick coat of fat that cnrelopc!) it ; then 
turn the inside out. and wash lliu ftiou ont ; soak 
it in water for a day or two, then lay it nn a cloth 
and with a bone or wood knife, scraj)e off the 
internal coat of the stomach, wash it well, and 
dry it with a clean cloth ; thrn turn the crop, and 
b^iu the outside by IItkI making an incision 
through the external coats taking particular care 
not to cut through tbe uiembrauo ; draw the coats 
at once over the neck, which mttst be ciit long for 
ffteater couvenicncc in using tbe ballouu when 
luiflbcd. Proceed with the other neck in the same 



ofthj 
rwtrd^H 

'Mion. " 
nn la 

LT. or 

iinoiftj 
out^l 

J 



wav ; tie it firm with silk, and cut It clow to tl 
body nf thr hnltnrai ; il muxt 1m- tlicn diste 
with wind and Imm; up In dry. Tbvy mar 
painted and Tumiihcd, hut will nnt require 
pmperly prepare*!. They may be wade 
enoui^h to contain a gallon of gas, and ao Light as 
to weigh only thirty grains, 

on of LemoHM U nude from the rind of 
fmit, by soaking, i)rcaHing, boiling, and after 
skimming off the nil. It is also made by distillation. 
EtMemee of LemoHs i§ the above mixed with spinta 
of wine, tliough the oil is often called eneocc. 
Syrup of Lt-monB U the same boih?d with nmr. or 
it may be made thus: — Rub the rind of a km 
on to loaf sugur. till all the oil cells on the 
side of the rind arc broken — then diaaolvc 
sugar in water. 

Printing im Gold and finnur.— Take japan 
gold size, and grind in it a yellow — any kind will 
do, as the color is merely tn give it a little 9trnng«r 
consistoncew and to cover any imperfection in 
printing. When the site is prepared to ihc co 
ftistcnce of treacle, it must he applied to the xy 
in tiio same niauncr us printing ink, and when 
impression in taken il is then covcrcU with fi 
gold bronze, by ineanit of a hare's foot. In : 
caiiea leaf gold is applied, and prrsacd on with 
llltle cotton wool. Enamolletl jiapcr or cards a 
the l>est for printing in i;old upon. 

Printiug in silver and in hruoze is conducted t 
the same manner. 



CORRESPONDENTS. 

Old Emiubi Imk may be hul of Mr. \V. G. Adianl. 

hittM, LoMdoo. 00(1 uf ail Stktlotwrt. 
Puiwhan'i CurTiiT <L>r MvMirB. H)4ill« and MerinolC, 

ntrsUr Kuw. Louden, utd uf tbe iBvantor. Oxford. 
J.ti..V. — CxMKNTa roK. Glaos — See V«iMM«ver'> ComMit. 

Vol. 1. To Ukc Grease from L^aUier. tbe b 
%iiow gf It to lay upun tiiv jilncv a |ia*tv ni.i 

earth and but Mater; tbe next Jay, if dry, bni' < 
J. NiCNLiM. — \n irett spUidle tbraugh IL, wlU aot 

power of an eloctrleal c^'Upder. 
Latiib Ciivcai. — Net powening the cocipniuid lath* ckac 

oat yet a roM eoclM, wa euobt ecwUmMi ihkt uibject, 

leu By tbe aaalftasee of eurvwpimdefitv. 
J, GAKLAvn. (Llit>oa.>— We an obliged for bin leuer. be' 

upon eomparlaoo. see that hii blowpipe u but a 

Uon of that of Mr. Palmer. menUooed m Nn. ^L 
B. B. — To dectioipoM water, a Kreatar heat U rcquiilt* 

the oombuitioii of tti hydroBi*n anennrarda yieM 

poaalng itcftin througb a furaacB, damtM catbcr th«^ 

cresMB the t-ITi-ct of tbe fire, 
H.V. — Ure*i DicUonarj' of Cfaemlftry b noeKr- 

rrft-rmice, but Draode'a Cbvmlalry wUI au^^ 

poae better. Aj to tbe tfuery on the wedgr^ 

be oo mollou In i*ttber- 
W F — The fault does nm lie with tho [•olidi at the 

but nM)«t llki'ly 111 tbe galvanic caniireUun*. 
A.^Th« profterty of odc lagredl«nt la no crtlerion of 

prnperly of a mlxuire Utto which It eDter*,. He may U 

to )lt|ani potuuue. 
T. K— Thry itre made of Puller's euUi and a lUtl* pflat 

wilb any Ibliig li> cojdr llioin. 
G. TuHLiN — Wu aball be niuebobUgid rorhta< 

parttculiifly Tur hia ••xperimcntK. 
J. W. CcuL— llie whole of his qucrlei tnuit be aMwmadl 

the MgaUve. We hive no recoUectiott of CMUvb^ 

eonimiuilcaUun he aJladee to. 



CutiiniuiiicatioM, Boulu !v*i Ilert<>w. 
iraUod, ate, lo b« addrened b> Ui' 
Preacut Street : to the Prtuter ; or i 
Letten muit be p«et paid. 



Printed by DPaancia. fi. White Horw l^ae. Mile i: 
Pubtlibed ever) SAMnlnT by W. liainAia. It. Pa. 
^ Row, and may be bad vi all BwhwUen aad Sewai 
Towa and CuiuiUy. 



106 



MAG.\ZIXE OF SCIENCE. 



THE mORAM\. 

Auovr. all tlie rontrivftocrs to grati^' the poblis 
carWi^y tfai* uIkjti; fiUitittiaii •ftanJ* rerUinly pre- 
nninmt. Tlu- iiiipoiing Dingnificeuce of the subjecU* 
the !«plfti[liiur of tbr pairttingi, the rivid Uluiioa of 
the scene — all conspire to render it ati ofyect of 
supreme interest and delij;ht to this sight-Mekin; 
nation ; aud llie populartky which it hiu attained, 
foondcd on the nire and permanent basis of real 
ejccdlencct is a certain indication of its intrinsic 

•Yalae u a work of art. 

The invention conMttd in placintj; the pictures or 

rpajnCed vcencrjr within n building so cuustructsd, 
that the aaloon or «inphitbt.>atre containing the 
apcctaton may be caused to rerolve at ititerraU, u 
mMj be desired, for the pui^tose of brio^inf^ in sue* 
oeisioD two or more distinct scenes or pictures into 
tbe field of view, and without the necessity of the 
spectators removing from their seats. Prom tlus 

••rnuij^nent of the revulviog saloon, the scenery or 
picture* themtelves may remain stationary, and will 
tlicrufore admit of the application of an improved 
method of distributing or directing the duylight 
upon or throtigh them, «o as to produce the efTccts 
of raryinj^ the light und shade in a more pleasing 
nunncr than has othern-isc bw.n aj^complished. The 
effects are produireJ by uiciins of a aumhirr uf culured 
transparent and moveable bliitdft or curtains, some 
of which are placed im»d ike yichtrt, for tbe 
purpose of intercepting and changing the color and 
■hues of the rays of liglit — which being pemntled 
to shine or pass through ccrtitin semi-transparent 
parts of the picture, produce many carious changes 
tn the appearance of the color, in }n'oportian as tbe 
colored blinds are moved up and down. This 
motion is performed in a peculiar order by the aid 
of oordi coiuuetcd with the machinery, whi4:h wv 

•4haU prwently describe. Other colored trans[urei)t 
blinds are situated above and in froat of the picture, 
which are also moved by Hues, and by that meflns 
distribute or direct the rays of light which are per- 
mitted to fall upon the "yice of the picture, and 

•thereby effect many surprising changes in the 
appearances of the colore of the painting. 

Fij. 1, in tlie engraviog, gives a horizontsl plan of 
the boildinK in the Regent's Park, in which arc now- 
being exhibited two magnificent pictures, each of 
them consistiug of several thouund sijaarc feet of 
canvas. A khows the plan of the revolvitig saloon, 
eonvenicntly hlted up with n circuliir range of boxes 
and scats at the back part, and with sc\-eral rows of 
benches in front; the mnsining space is a carpeted 
floor luid upon an Inolined piano, for ipeotaton 
who choose to stand. U B aliews the situation of 
one of the picturoa ; and C C the altnation of the 
other. O D are two lurgo windows, 5tted with 
grniind or M<mi>tran»purcnt glas4. to admit a portion 
of lif(hl behind the picture. The saloon is a building 
of a ryliadrical form, and hns a spacious opening, 
Z, in one side, fur viewing tho picture through. 
The diiors fur the adiui&Ainn and departure of the 
company are situated at S S and Z Z on the opposite 
aide. Tl»e spact'3 between the opening of tbe saloon 
and the pioiures is inelosed above and on each side 
by light Si2r««na, formlni;; a kind uf vista, (as acfln 
at fl (I and h k\ which, eoncculing the margin of the 
pietur- in a oerlaiu ckgiw the effect of 

panor 

Kii,'- _ .,,. . „u a vertical position of the build- 
ing and apparatus, in the direction of the dotted 
Ijno X tlrawn on the plan, and the letters of re^ 




femco are the same in both of the figurea for 
corrrapofiding parts. Consequently A rfiowa 
■alooa, tbe walk of whkh are rlcguitly ! 
with 4rafery and painted d^irP4 ; and t 
which is of a slightly conical tig^T- 
onunnifnted with a tranepamit 
designedly admits of but a very 51, 
skylights placed above. B is one uf the pi 
suspended from above, and kept in a proper 
of teninon fay umidl wrizlits hong on at hoi 
also at the side*, tit which place the tines 
weights |Miss over small pulJL'ys fixed to a 
rail not shown in tbe engraving. Before tbe 
D tbe colored transparent blinds are sovj 
tines, so as to be capable of moving up and doi 
In order to pass by and overlay each other; fiw 
these are represented at f, but there may be a cotii' 
stderably greater number used, which wit) depend 
entirely upon the nature of the painting or scalar) 
to be exhibited, and mofft, as well as the arrmfigv 
ment of their movementa, and also the color of llH 
cloth, be determined by the judgment of tbe patntar, 
P bhows a targe sky-light in the roof of tbe pit:tun 
room for the admission of li^ht upon the incc d 
tbe picture ; tbis window is likevrias fitted will 
groond glas<, and furnished with CranspM^nt foloavd 
blinds, as seen at F F, which mofe upon fa 
joints fixed to their uppermost ends, so as 
eapable of moving into rhe dotted positioa, 
permitting the rays of light to fall nao' 
upon the face of the picture ; when they are 
up as shown to the figure, they interice|>t part of 
light, and when brought fully up tb^y Bi«y be 
to close up the window entirely, and thereby 
all the rsys of light to pus upon the piotore 
the colored shades, so as to prodioe 
tbe shades and tints upon the picture. 

llie colored blinds are moved by cords 
which proceeding from them, pass over si 
near the top of tbe building, and tlim 
are attaobed to a long lever or balance, G H 
moves upon a centre or fulcrnm at A. This 
the apparatus is ritaated in that tntermediata 
of the building between the two picture 
Roen at k in the plan. Fig. 1. The lines K 
over small pulleys, 4', and over leading puUry 
silnated at tbe end of the roof of the baiUbll| 
after which they are attached to extremities et tlH 
blinds, P F, in order to close or open 
There sro five pairs of these blinds intlw Irngi) 
the building, but only one pair eihlbitcd in 
figure, The cords marked L, and tboaa msrked M 
proceed over Bmsll pulleys in tbe roof of the 
ing, and are then attached to the hanciwg 
The lower ends of these cords, L aw 
attached to the lever G H on opposite 
fulcrum, consequently, when tbe lever Is 
its centre, some of tbe blinds will ascend and 
descend, so as to pass over each other, and 
different tints of light : but no preciae or 
general rules con be laid down for these m 
they miut de|iend entirely upon the oatnra 
scene and the Intention of the artist. Whea 
desired to {vroduce the change in tbe ligh< 
shades of the picture, a workman draws tbe 
of tba lever slowly downwarda, bv tsmii^ 
wbuk P dunra in Fig. 1. and also by 4ottedl 
at P in Fig, 2, where two ends of a rope pi 
over pulleys, and are attached to oppoaite 
the lever G II ; this rope winds round a 
which is turned by a pii\ion and cog wbeel 
the windi P| snd the cuds of it psM off (m 



MAGAZINE OP 8CIKNCE. 



tW 



ot tb< barrel. fO that » TAriety of flhangc* \» 
hy tumlnif the winch rouml ui contrnrj 
A btUnce weight is sttaclied to one 
OlA ti ttM^lsrer G H, for the purpose of baUiK-iii; 
of the blioOi. The sxtcoc of motion 
VMMMiA oolorcd blinds may require to 
rammiinicMti ft to Uictn, con be obtutkcd by 
nc tiwir Hues oc cordt to the lever G U, 
ti> or further from the centre of motiaiu 
Iki tfooT of the revolviug laloon is supported 

racvjAtroag timber b«me-work, which cousUta 
MBitnl ebaXk or ixle, a, hsviog Iwclrc limbers 
a«* ninilAr to those at pp^ aminged round it at 
liiUBCca in the maoAex of mdH ; tlio tf^itrc- 
of thr»e timber* are connected hy upright 
ftud the whole framing further strrngthened 
brace* and cross- timbers, which, pro- 
beiD one arm to the next^ arc fimily bolted 
aiLd form a |>entM(oaal fraaiinK. Ttie 
'thabera serve to carry tlie bearings of twrlvc 
tfnme iron alufU, which form the asis to tweK« 
-.vheels or roUiuv, two of whirh are shown 
i beve wbeeU roU ro«nd upo« the surface 
li. I urcuUr uctdl curb or ring* hrmly bolted to a 
of auaonry sitanled n|toa the top edge of the 
r wall U 0. Tlus wall having to sapport 
'^ ssynltuig amphikhaurtt abova, has » very solid 
[i.:jViii tn-.tfiy feet below the sarfaoe. The ooitral 
;boJ with a pivot or gudgctoo at its 
, which works in a bnist sti:p-pieoe, 
\)i »iili ud^uiting BfiewK, aud aecnrcty tise.d on 
r of mutoary. The cyliuddcol pare of the 
k abov* tbo Aoor is comimsad of light wood 
■aCernaUy decorated as before mentioned. 
\nmi 0I ths ihIouq is furnished with a gudgeon 
fiHtLin '.he ccolre, adApled to turn round in a 
adlxcd Ui otu of the priacipuls of the main 
la aecn at I. It shews a fky-light for nd- 
( Ught tliruugb tb« tnaapareul ceding of the 

i €Sttmit «t the cirdo described bjr the revolving 

«f (he nJoua, in exhibiiiog the two pictunrs 

ly, forma an arc of about 73^; and dnrim^ 

tlinl the saloon is in moLiou no com{Miiiy is 

to go in er ont ; hot when Ihd a|>cning S 

ia the proper sitoatioQ opposite to eithaf 

fKtures-, one of the two doori, « ;, of the 

will be found to correspond exactly with one 

door-wa5S respectively marked s ; shown in 

brick w&ll aurrounding the saloon» and 

•• vpcn a direct entrance to it. IM the 

of Hits drcolar wall a suitable room ot R is 

for such of the compoujr to wait in that 

• •ment the saloon u in motiun. 

-^' only to describe the method by 

-r.. ' ..., nf the saloon is effected, 

ry limited space allowed 
> |H>rt uf tlie mocliinery 
li not rery dear ia the Tig. 2. K portion 
of n wheel with eogs, o, is lirndy fixed 
ti ttr osatrtl shaft 0, so that its cogs ouy be 
fl^«|ed wsth the cogs of a pinion fixed upon a 
iKbakl sfciA. vUch hoe a beviUed wheel at its 
bmr rtmmityi this wheel is engaged with the 
1Mb vi aaoOicr brvilled wheel placed in a vertical 
I and as the azia of the lost-mentioned 
aUo a fxig wheel, they revolve together. This 
il Kt in motion by a Kmall pinion, 
•paralad npon by the turaiog 
-"h a fly wheel apoo the lamc axis to 



1LLUSTB.\TI0NS OF THB LIXX^AN 
SYSTEM, NAMING PLANTS. Ac, 

fJieiaMCiiJntm page i^.J 
The observations on pages 59 and 59 will readlljr 
RUfrgeat tliR method to be odoptcd in finding the 
name of on unknown plant. For esanipir, suppose 
we gal-lier one from the fields, ood posAcas some 
book whirfi «v know contains a dcscripliun of it. 
We may nut be aware of tht- name of the plant we 
have gathered, and coftsequently know not in what 
port ef the book such a description i« to be fvut>d. 
To ssecrtain this, wc unit proooad as follows t— • 
First, dkrrcttng tMir otumtion to the fiowers, we find 
UuU there nee tixa dtsUitct staroons) friw which wfl 
cuiicludu it to be of tke class Featandtia. Neat wo 
obst-mr Lhr niuuber uf styles ; there hiimg but ooOt 
the order it beloof;* to ta Moui^fcyria. We must 
now turn to Ib^ psoper class and oj dur in the book 
we po&ses.«. and then wa shall 6ad a sariatSLu^ 
Rmcra arrangrd under mch other, and vpry often 
cnllortcd \nto litllo gronpa. Reading uver the cha- 
racttTs uf these gviiera, our plant will agree with 
only one of Ihom — fur iiistoiuie. with rriniuln, or 
the Primrose fanitly, whusa cluuacters are, ndyx 
tubular and firc-toolhed ; corglbi salver* shaped ; it* 
tube cylindrical ; its mouth Open. Capsule ojicning 
with ten teeth. 

As these characters belong to no other genua. 
whatever, we cannot err thus Car, and it euly re- 
mains for us to discover what sptvi- - '" " nla 
we have plarkrd. Icr this pnrpusc w. 11 

a little further in the book, where Pn u .._ .re 

fatly deseribcd. and which the hHtrs. or e«r own 
ohferratlon, vHlI easily direct as to. Hero ftva 
British species arc described as foHowa : — 

* La.\VK« OKBSN. FtOWKILS TBLLOW. 

OyimMon /*r*»ro«r.. . Flowers single on the stalk. 
(Ulip, . Flowers many on the stalk ; corolla flat. 
Cmeatip . . Flowers many 00 the stalk ; corolla eon- 

cavi;. 

* Lkavkb hra^v. Fbowicnn piNit. 

BirtTt-rjft Primrose. . Leaves cnuiota; calyx ob- 
long, ovate. 

Soottuk i'rsmroM.. LcaTCft dentate; calyx swelled 
out. 

By attending to the above it is easy to know our 
phiiit. for iu it agree!) oidy wtlh the first dcMfip- 
tion, it must be tlia Cammon I'rimrwte, that "meeit 
nnil Koft-ryed rmhk'm of childhood," which greets 
UB with tlie promUe uf coming spring, and which 
brightens the mossy hedgivrowa with its smiling 
yelluw flowers. 

The oU)VQ niertiwf of naming unknovm plants is 
appliu'ablc iu all other cases,, both on wild and 
garden Ouwers : it implies but little Ul>oue, and 
uceupics, except in difficult cases, but Utrle time. 
Still Co the young botanist it may appear diflirntt, 
but let hira remember that every step In hi* progress 
renders what is to come more easy. When he 
knows one of tbt^ above .ipccics, be has but to look 
at four descriptions instead of five, whenever he has 
procured a tiecoud *iiec»c8 — a third x* sLiU more 
easily found out* and so uu in all iustancca. 

The followiug ubftcrvatioas on the varioas Ijn* 
nacaa clones, and exumplca of some plants found 
under each, will much assist the student's gc&cTal 
knowledge of classification. lie may gather any 
plant mentioned, and compare it with the character* 
of the cUss. 




108 



MAGAZINE OF SCIENCE, 



CliiBB I.— MovAxsiLiA. Two ordert 



% 



ConUinlng plaati wllb only I ■toju — , and I or S ityW*. 



J. >i 



A BfniiU c1juni» eontaininfr iimon^ its hjirdy plnoti, 
the elpgant Strawberry Illite, and the Red Cn- 
tnnthos, otherwiie called Red VnJeriui. ItJ hot- 
bonse pUnts an many of them interesting and 
bcoutiral ; amonf; them are the Gin^r, the Arrow 
Root, and the Tormeric. The Saltwort, the Watfr 
Slanrort, and the Mare'a-tail. are alt that EnKluid 
Mils her own ; and thcae, which are mud |iUata, 
Imt little besnty or interest. 

ClsM II. — DtANOMA. Three orders. 



y 




CflBtidBhn plaab mlib t lUmna, and 1, 3. or 3 stjla. 

i V.ir 

Ad interesting, though small cksa — many of its 
flowers ore both beautiful and fngraiit. l^e Jas- 
mine, the Ulac, the Rosemary, aad the Privet, are 
among them. Here, too, wc find the Olire, the 
Pepper plant, the Sage, (of which there are no less 
than 170 ipeclei,) the Veronica family, the Schi- 
Bsnthtts, and the curious little BLuIdcrwort, so 
remarkable for its root. In the second order is 
•Imoefc the only Grass which bears a scent ; it b 
ciUed the Sweet-scented Vernal Grass, and in the 
■pftaf oorera most of our dry and road -aide pastures. 
It is a fevorite with the cattle, and, when dried, 
will retain iU scent for years. 

CIui lit.— Tkiaxdaia. Three ofden. 



Plsata «ritb 4 ttasimu of tqual Itsf th. and I. 3, « 

b.V.ir 

We find but few p.anti, with four 
among them are some of interest. The H 
the fields is well known to us all. The Ti 
reeeptsole is so valaabte in fulling cloth, 
lesTcs are so farmed as to retain the < 
them, belongs here; so also does flu 
glossy'learrd Holly. The Scabioas, 
grass, and that vegetable ingrata, the 

Class T.— FsKTAKo&iA. Six ordoi 



^ 



rianls wUb 5 



a«id 1 . >, t, 4, S, ot maayt 



iM.^xm.«t 



'^ 



CsttUiabf plaau wlUi 8 fUrmiNi. u«t I, 8, or S ttylvt. 



\y.^ 



A elan cxtensire, important, and Taried. It 
contains, in the first order, the Crociu, the IHs, and 
most of tfa(^ bcAUtiful bulbous phints of South Africs. 
FoUowtng these are Domerons nuh.like plants of 
Mttre growlii, and the sacred Papynis, the plant 
llroiD whose pithy, nuh-Ukc stem, Uie ancients pro> 
cored there first, and, fur many ages, there onlj 
paper. In the second order is that numerous and 
valttable tribe, the Con, the Gnnes, the Reeds, and 



Fentandria containa. no leas than aboat< 
of the whole flowerinic plants. It begins 
rongh-lttTed kindi. The Bugloss snd the' 
arc among them. Then there is the hrrt 
•• For^-me-not,'* that blomms bright an 
the rippling stream. The curioin Piaipl 
Poor Man's Weather Ohus. is its near aj 
Then follow the aspiring BeU-bine. the \(M 
roac. and the fragrMt Violet, theCoffecthel 
the Capsicum, the Bobiam. the luarioos G| 
noble Teak tree, ^thit lord of the Asiatie 
and the shining Cnrrant. The poisonoos I 
the Nightshade, in which src the Egg pk 
l*vc Apple, and tltc PoUtoe. bear tbem 4 
in the first order. In the next com« that 
tribe, the Umbellat* plants, as the C*n 
PKTsler. the Parsnip, and the Hemlock, 
order Trigynia, among others, are the GneU 
the Elder, and the Sumach. In the oi ~ 
gynia ia but the Grass of PamaMUs, « k 
of oar mountain pastures. In Pi-nlagynid 
thiok-lcsTed CrasBuliia, the useful FUz, thf 
and the corioos Sundew. 





thaSogv Cane. 

CkM IV,— TXTIU.1«DR1A. 



MAGAZINK OT' SCIENCE. 



Wl 



TUs oUm cLunij our Dodce from the beauty of 

■MBC vf iU examples, no less th&n frooi the utility 

if ttit rest. Mlio hu not obMrred and atlmired the 

rilpnt Ibnn* colon, ind beauty of the Lilies, the 

iHovdrop, the NardMOJ, the Tulip, the iIyiK:inl.h. 

isd mlaiust all Uic ntt of the balbs ? Tltese are not 

tH, rreu m the 61st orJer, for we have the noble 

&CUIU1 or FUnUln tree, tlie Aloe, Ibe Fine Apple, 

thr Bamboo aud Rattan Cane, tlie Piiu Palm, Lhe 

Yarra, Iha laly of the Valley, and the Ai{>ani^B. 

1W Ric«, Uwt valuable plane which pruwii in water, 

Thrrr nothing eU« fit for hnmnn food will flourish, 

mi] u'riirh nippUes with nutriment no less than 

■•third of the whole human race, belong to the 

Hkl onler of this class. In the third are placed 

Iar<ge family of the Docks, one species of which 

^ABttutBonSoneL 

(Cbntimud an pggr 112.) 

FROZEN WELL. 
KtAft Owe^, oecars this apparent contradiction of 
Mtnrp'f lawn, which is thus described by a correi* 
f(tt\'Ur>i m SitthMtm't Jcmmd/, 

The well is excavated on a table of land, elevated 

Ams thirty feet above the bed of the Sus^iuehanna 

Mfer, and distant from it three-fourths of a mile. 

JW irpth of the well, from the surface to the 

is said to be 77 feet ; but for four or 6ve 

bk the year, the mrface of the water ia 

•O aolid «• to be entirely useless to the inha- 

li|tat». On the 23d of the present month. (Feb.) 

[■WBfWiy ^th a^friend. 1 measared the depth, 

tolfNikd it to be 61 feet from tlie surface of the 

attk to tlw ice which covers the water in the well, 

mi tk<ft ice we foond it impouible lo break with a 

L weight attached to 1 rope. The iidee of 

irr iienrty covered with uinisca of ice, 

is; in the descent, leave but abont a 

I'uneter) at the bottom. A tbermo- 

IthQ bottom, sunk 38*^ in 15 
lhe sun, and 30" at the bottom 
_,., - - A\ has bern dog 21 years, and 
4ai tetonDed by a very credible person who assisted 
ll Ifte eusvation, that a man couhl not descend 
b««fl( in it for more than two hours at a time, 
ma «iih e^lra clothing, although in the mouth of 
Jbk; and the weathei' cxceaaivcty hot. The ice 
natil very late in the season, and is often 
p to the monthi of Jane and July. Samuel 
drew from the well a large piece of ice on 
la tMh dsy of July, 1B37, and it is common to 
Mil tkei« on the 4th of July. 
; Th> «cll &• situated in the highway, about one 
lAi Qorthweit of the villnge of Owego, in the town 
■4 eamtrf of Tioga. There is no ntber well on 
1m tiMft ol land, nor within GO or 80 rods, and 
Jbk that |H«*ests the same phenomenon. In the 
MBMlkia, hO rock or slite was thrown up ; the 
Wribr ii Dwvcr alTected by freshests; and is what is 
■■Aj denomittAted ** hard," or limestone water. 
A Uglu«4 flandte bein;;; let down, tlie flame became 
and thrown in one direction at the depth of 
i9 ftwi, Wt iraa qaite still, and soon extingniahed 
tflte bottom. Feathers, down, or any Ught sub- 
wheo thrown in, rink with a rapid and 
Kiisi tied motion. 
WnfM^^T SiUlman. in sttempting to folre this 
;><1 dUGcolt problem, obeervea : At 
rfl than 60 feet, water ought not to 
^^■'^•Ud have nearly the same tem- 
(A the earth's cnut, which is 
'7 atflkospberio varUtioiu, and 



solar influence, being of course not far from tl.e 
medium temperature of the climate. Could we 
Buppo» that compressed gases, or a greatly com. 
pressed atmosphere were eecaptng from the water, 
or near it, tliia would indicate n source of cold ; bul 
oa there is no such indication in the water, wc 
cannot avail oorselvis of this explaualioo, unless we 
were to suppose that the escape of compressed gas 
takes place deep in the earth, in the vicinity of Uus 
well, and in proximity to the wnter that supplies it. 
Perhaps, this view is countennnred by the blowing 
of the candle at the depth of 30 feet, blowing it to 
one ^ide, thas indicating a jet of gas which might 
rise from the water as low as its source; and evvu 
if it were carbonic arid, it might not extiu^uish the 
candle, while descending, as the pas would be much 
dilated by rommnn oir ; and still, in the pmgreM of 
lirau, nn accumulation of cnrbunic acid gas might 
take place at the surface of the water, aul&cient to 
ejctingiiish a candle. 

LITHOGRAPHY. 

(Bendmed from jta^ »5.) 
Uthogrophie Stones. — Any stoue which effer- 
vesces with an acid, which imbibes water with faci- 
lity, and is easily pcnelrmtcd bf greasy subslances, 
is 6t for lithography. It ii well known tliat rnr> 
bonate of lime fulfils these condition! ; next to silex, 
lime is the earth found in greatest nbundance on the 
surface of our globe, and chietly in the state of car- 
bonate. It is found, first, lu niassca in primitive 
beds, and almost always of a white color, and in a 
pure state ; Becondly, in transition beds, in m.i^i^M's 
of different colore, proceeding from Ibe dctritna 
of the first ; such are marbles ; thirdly, in bD<U of 
later formation ; in tliesc it is found in abniidant 
strata ; but it is neceseary to ohoose amongst these, 
as these beds or depnsits formed by water are almost 
always of a coarse texture, intermixed witlk crystals 
or filled with shells. 

By this it is easy to sec that litbograpliic stones 
are not scarce ; from the coarse calcareous stone 
which serves for buildings, to the compact calca- 
reous onea, which receive the polish of marble ; on 
infinite variety of other stones exist, wliich contain 
with lime, silex and alumina, and the two Utter 
even to excess, and which are all more or less proper 
for lithography. 

Lithographic stones may consequently be found 
in chains of mountains, on hills, and in plains ; 
those, therefore, who are in seardt of them, onght 
tu be provided with a smalt buttle of nitrin acid, 
and whenever a while stone is found which doca not 
strike fire with steel, it must be tried vtith the acid, 
and if an effervescence takes place, it is a litho* 
grapluc stone. The following are the rules by 
which the best may be selected ; — 

The best Utliographic stone bttlierto found breaks 
with a conchoidal fracture ; it is of a fine homoge- 
neous texture, its color is a uniform and ycUowi^ 
white, being nearly similar in appearance to the 
bone stones used in sharpening razors ; on breothing 
on them, a slight alominoos smoU, (similar to Uot 
of pipe-clay,) is perceived. 

The quarry from which the first lithographic 
stones were cxtmctcd, is still that which furnishes 
them in the greatest abundance, and of the largest 
dimensions. It ia situated at Solenhofen, near 
Papeulieim, in Bavaria. No quarries luthcrto 
known in France give atones equal to the German 
ones. 



tio 



MAGAXWE OF SaENCE. 



have been found near Cha- 
E, wtuidi in itoine reipects have » grent 
adnatig* mwtit the Bararkn ones j they ue nuch 
harder, of « &n«r (aitar*, they preaerve mucb 
Wtter the toft tinta ia eh^k aofniTiaft, and the 
hnpmaioaa are mach brighter. Kor these reaaoDs, 
the Preach atonea woutd bo &r superior to the 
Ocnmnt werv they nut intenperaed wttli innn- 
nenMa apoCa and dciecta, so tbat it ii eatremdy 
difficult to find one, 18 inotiM iquare, whidi u free 
from Iht^m. 

We have tried Knae atone* eitractad from • acw 
quArry, found near CHateUeraalt ; they appear to 
posseaa all the neeenary qualitiea : they may be 
procured of any «ixe ; they are white, alightly hi- 
clintu] to a grey, uce$sively hard, and highly alia* 
niiuuui ; ,tbey absorb both wvin and grens* with 
equal aviclity. Line* drawn upon thia atone print 
with great purity, and it ia perfaape paeiBrable to 
any other for ink dmwingi. 

Nut to tb«u! Btonef. which are the oidy ooee to 
be employed for highly fioished drawings, we may 
rank white inorbles, which are not bo proi>er for 
lithngra|ihy. After these, aome the common cal- 
cnreoiu atones, which prodaco drAH-ingi of rarioua 
quahliea according to the more or lean Aneneaa of 
their texture ; and last of all, the roaraeat caieareooa 
atones, which from the namber of foreign eubitancea 
tkry i^ootain, cannot be employed in lilhngmphy. 

Sawing and Polisfiint/ Me Slonet. — In order to 
withstand the neoestary pressure, a stone a foot 
ftloAre mu^t not be less than two hichee in Ihkk- 
ncaa ; and one three fcet square, most be at least 
four inches thick. 

When atones are e great deal thicker than ia 
aecenary, they may be divided by a saw and aaod, 
■a ia done with marble ; and after they hare bom 
squared, they must be rublwd face to face with 
Kuul and water, and the edges rounded with a file 
and smoothed witli pumice<atoae, using the sand 
fiiirr anil tiner by degrees, until the surface is per- 
f<fcily smooth and even, when the stone will be 
really for tlie dranghlsman. 

Dificmit grains are given, according to the 
iiKturo of the drawingi: fine and delicate drawings 
require a very fine groin, while bold and spirited 
one* require a coarser one. 

Hubbiitff off Chalk Draicingn. — When a stone ia 
done with, and it is wished to rub off the drawing 
which is on it, in onler to execute another, it must 
be first rubbed with sand until the tines of the 
drawing have disappeared ; it must then be washed 
with a mixture of aqtafortis and water, (in the 
prvportion of one port of add to twenty of water.) 
Ilkta operation is itidiisjiensable in order to destroy 
the former drawing, which otherwise would re- 
appear in the printing ; It ia then rubbed with fine 
Baud, and tn»tcd in every respect aa la the firvt 
pnqiaration of the stone. 

Pre/iaratiou f^f Stonet for Ink Dnatinft, — The 
stonn having been prepared with fine sand, aa ia 
done for ch&lk drawing, mu^t be well washed, and 
carried Co a table perfectly free from aand or dnst ; 
they must then be rubbed face to face with pow- 
dercd pumice-stono and water ; when per^wtly 
amoth. they muat be again washed. This being 
dime, take n large pumice-stone, of « linQ texture, 
BOd rub each atone scpomtely with it, und with a 
drcnlar m<>tion ; this most be continued until the 
Atone ia pulishcd, auj perfectly fixe from grain or 
tcratcnes. 

When it it wished to give a still higher noll»b» 



the stonea ore oftoa tabbed vitb a nf ana pi 
stone well powdered snd afted \ \k most be «OiN] 
wards waahed ud r oh heJ Tinlimllj- with • llMi| 
r«g; the atone it thm seedy for Ih* Anaghtem^ 

Hub^n^ nff hUt Dm/imp*, la oeder la rtiit of 
ink drawingi, the aurface of the attui' 
strewed with powdenul pcmice-aCem u>. 
another atone laid over it, and thus Chry uiut kl 
rubbed fiice to Cue natil the drawing d'tay]prsh 
ocid and water arc now to be p o n ro d oo Ae imi% 
which must be afterwarda waahod nd ppryoiel 
afreah is la the firat Jnatannt. 

f f>oriBiie< eo p^g9 19^ 

ASSAM TEA. 

It will be remembered that, 
the lea-plant being indtgci: 

Mr. C. A. Druce vraa sent tbi^L^- , .isic i 

country, and woa appointed raqwriniewlenl 
culture. He then procoedvd to raiae 
and, in the year 1858, tranaoulttd W 
eight chests of '* Aaaau Ten," coeIl 
320 lb*. it appcara. alao» that Mr. 
dr&wn up hu oecond Rapoit, whkh bM 
icoted hy the Tea Committee anfolatod by 
Bengal GoTcrmnent. 

Notwithatond'mg the tronblea in whkk tl>e fn 
of Aasam has been involved, Mr. Orice boe 
getkcr diaoorered 120 tca.tracia, aone of than 
cottcfkrive, both oo the hills aaul ia tiiv pUfaH 
whenot a lufficient number of leeda and 
might be rollecled, in the eoursa of a few ye«M» I 
plant off the whole of Aaoanit 

In 183B, on going ever one of the kitla 
inipore, about 300 feet high, Mr. Bnaoo 
a tea-tract between two and three aulea in I 
the trees were moatly a> tluek oa they fKxaU 
and tba tea-ae«d« (aniaUar than ha had aeea k 
literally covered the gronnd : this waa in tba : 
of November, when the treea bod 
fruit and flower on them. One of the Urgeat 
woa two cubita in circnmfiereBCfl, and fully 
cobita ia height. At the foot of the bill waa aa 
teo-tmct, and daubtle«g many of the Na^ 
covered with tea. Mr. Brace croaaed tiw 
river at the old furt of Gkergong, aa^ 
towards the hills, olmoft inniedi^ely flU 
tea : and iu two days journey ka aaw tUrlaa 
Farther south^wcfit, the small hills adioinisf 
hill were covered with tca-plonta. " IVe 
of the tea on the hilla ore of a pleaaaat, 
fragraocG, unlike tbe emell of othsr tea-pteta 
the leaves and fruit appear die vme. Thia 
be a deifgfatful place for tke raanttfkctBra of las, 
tbe country is well populated, haa abuudauoa 
water, and gr&in ia cheap. There is a asall 
called the Jbaugy river, at a distance of t«"> 
walk : it is navigable all the year roan-' 
canoes, which would carry down the tr : 
place ia only one aod a half day'a }0" < 
Jorafaant, the capital of Upper Aaaan.' 
west of Gabrew Porbet, (about twodaf* j' 
a village hihabited by a race called N'^ 
caree from Ibe eastmud, where tea abovi • 
oldest man in this village told Mr. Brace 
Ilia fiitbor woa a yoang man, he bad aad^i 
many others, andseMlodat Tipttm,opposi< 
that'thry hroogkl the tca.pbnt with 
planted it or the T^nm hiU* where it ex i : 
day; and Mut wkan he waa abnat aiait"' 
ago, ka w«f oompeUod to laava tSpoft^ ui' 



MAGAZINE OP SCIKNCE. 



lit 



md take iheltcr nt tfa« 
\»t BOW reifdM. Thb mm sud he wms 
fjf •«:«, and hit fethcT died « vtry old 
%* tti^r oti)y VAAfl mrl hj Mr. Bruce iii 
oeniA gin Kim any acccmnt of tlte 
Uie excvpliua of an Atiuni, who 
It wu Booka, or ibe first Kachftrry 
lltoai, who brougbt the Cea-pla»t from 
— h* Riid it wM written in his Putty, or 
Mr. Bmce found the old Norab mui*8 
; for the snpejiDtfnrirnt cleared the tract 
fbickeit, about 500 yanU by 300 : the 
MUi U9 fhther cut tbe plant down every 
, ttuC be mi^ht get the young Ictree 
^rt U accompanied by a map of Muttuck, 
Mad t^e rountry «e£t of the Boree Dibing 
tm\ng all the tea-trvcts that have been 
1 ; they are distributed oil over the diatrict. 
t docS nut prttirnd to %ay Ituw much tea 
ild all produce if fully worked. Until 
ily two Chinese black tea makers. 
native aasistantj ; each Chinaman, 
, cui only sapcrintoid one locality, 
a from the various otlier tracts, 
matt be broui;ht to these two places 
Hrnce, additional labourers must 
{doyul tn bring the Icavca from to 
tbe leaves, too, in the journey, 
rmeot, and the labour of only pre- 
Car in process that they may not 
morning is cxeessire. The men have 
: Tery Utc. and eonsequ^ntly the labour 
executed ; the leaves last gathered arc 
Tgee than they ought to be, for wont of 
and manufactured earlier — ixinse- 
U of inferior quality. This is men- 
the iarooveni£nce and expense of 
' te«>makcrs— 'ft disadvantage which 
with tbe luoceas of the experiment, 
ers that it will not become sufli- 
be tronaffrred to speculators, 
number of native tea-maDofa^turera 
to prepare the black and green 
100 available tea-manufacturers, 
worth while to take up tbe scheme on a 
Labourers must be introduced, in tbe 
, to gite a tone to the Asum opium- 
be great fear is, that three latter would 
comers. If the cultivation of tea 
i the poppy put a stop to in 
would make a splendid set of 
and tea-cultivotora. 
Um extent of the tea'tracts, Mr. 
to tlnse patches of plants which 
and doci not reckon the 
in Ibe forest and jougle. The 
lo thick as to impede each other's 
' innioff them, a snfficiant number 
found to fiU up the patches of 
• present tracts. Yet many tea- 
cut down, in ignorance, bjr the 
make Titom for the rice-field, for fire 
Many of these tracts have 
iMro vigorous than before. 

era that in Aasam, as in China, 

proitwce the Lett teas. In the low 

leen (o love and court moiature, 

pooUf b«t ranoing atreaoiK The 

iuiT« ibe water in and around them, 

heavy trc£.jungles. An extent of 

JOO will cost from '200 to 3C0 rupees, 

<k MfiDrdwg to the manner in which 



the miserable opiom -smoking Assaniflaework. l%ey 
will not permit tbeir women tn come tnlo the tea- 
gardens : whereas, females and ehildreti might ha 
profitmbly employed in plncklng and sorting leaves. 
But the gathering is hard work — tbe standing in 
one posithm ao many ha^ut oeottioM swelling In 
the legs ; as the Asaameae ]rfantB an not like thoio 
of China, only three feet high, bat doable that sise, 
so that one mnst stand uprigiit to pluck tbe l«Bve«« 
The Chinese gathor theirs squatting down. Tbv 
Asjiamcsc trees Trill, probohly, brrome of 'a smallar 
and more convenient size after a few years* enltiva- 
tion ; from trimming the plants, taking all tbedr 
young leaves as soon as they appear. siWI tnm lAta 
soil being poorer. IVanspl anting, Klso, heljjs to 
stnnt and shorten fhdr growth. The Chinese m- 
Bured Mr. Bruce, that the China planta, now 4jf 
Doenjoy. would never hare attained half their present 
perfection under (m years in tbeir own conntry. 

The sun tnatcrially aifects tht^ lenve^t for, ns 
soon OB the trees that shade the plants are removed, 
the leaf loses its fine deep green, and turns yel- 
lowish : but it Bl length changes to a healthy green. 
and becomes thkker than when in tlie ithade. Tbo 
more tbe leaver are plucked, the giratcr number of 
them are produced. The plants iu tbe sun have 
Rowers and fruit much earher than those in the 
shade; fiowers and seeds in July* and fntit in 
November. Some plants, by cold or rain, having 
lost all their (lowers, throw out buds mor« abun- 
dantly than ever. Thus, plants may be seen in 
flower ao late as March, (some of the China planti 
were in flower in April,) bearing tbe old and tbe 
new seeds, flowrr-buds, and full-blown flowers, aU 
at one and the same time. The rain, also, greatly 
affects tbe leaves, for some sorts of tea cannot ba 
made in t rainy dsy ; for instance, the Powehon^ 
and Mingchtntr. Tl>c leaves for these ought to be 
collected about 10 a. u. on a sunny morning, when 
the tlew has evaporated. Tbe PoKch<mg can only 
be manufactured from the leaves of the first crop \ 
but the Mxngvkew^ although it requires tbe same 
rare m making as the other, cnn yet be made from 
any crop, provided tbe morning be sunny. The 
Chinese dislike gathering leavca an a rainy day for 
any description of tea. Some pretend to distinguish 
the tea imade on a rainy day from that made on a 
sunny day. much In the same mam«r as they can 
distinguish tbe shady from tbe snnny teas, by their 
inferiority. If Uic large leaves for the black tea 
were collected on a rainy day. about savan seers, or 
fourteen pounds, would be required to make one 
seer, or two pounds, of tea ; but if collected on a 
suuny day, about four seerSi or ^gbt pounds, of 
green leaves, would make one teer, or two pounds* 
of tea ; so the Chinamen told Mr. Druce ; and 
from experiment he found their statement correct. 
The season for tea-making generally commencea 
about the middle of March ; tha stcond crop in the 
middle of May ; and the third about tbe middk ot 
July ; but tbe bme varies according to tbe raina 
setting in sooner or later. 

Wu now arrive at near tbe number of tea-planla 
cuUivated in Assam. Tbe China black tea-plants 
whiohwere brought into Muttack, in 1837, amounted 
to 1609, healthy and sickly ; and tbey moatly 
flourish as well as if reared in China. Mr. Brace 
collected about twenty. four pounds of the China 
seeds, and sowed some on the little bill of Tipum* 
in his tea-gardrn, and others in the nursery -ground 
at Jaipcre ; about 3,000 of which have come ap, 
are looking beautiful^ and doing very well ; hut the 



U3 



MAGAZINE OF SCIENCE. 



Chiu McdUngs on Tipam hill have been dectrojred. 
Itie Ajsatu aod Cbioa •eedUngs are near eacb otbcr ; 
,tbo latter haTc « much djirker appenrwce— tUere 
lay be about 10,000 of them. In June and July, 
'1B37, 17»OD0 yauDg plants were brought from 
MutUck, and planted out in thick tree lunglci. 
Six or eight thoatand hod prcriooaly been planted 
tliere ; many of thcae died in cun5L-qucn[?c of the 
butfiUues ronslantly breaking in among them ; but 
the reit are doing well, tliough in jeopardy of Ibc 
nhoTf enemies. 

la iSliB, 52,000 young tea-plants vere brought 
lirom about ten milea ditUnce from Jaipore ; a great 
portioD of these hare been Bcnt to Calcutta, to be 
forwarded to Madras. Should they thrive there, it 
is Mr. Brace's opinion that they will neror attain 
the height of the Aisameae plants, but be dwar£ab 
like the Cbiacse. Transplantation should be done 
in Uie rains, when very hw, if any, will die, pro- 
vided, alio, that they are remoTcd from one sunny 
tract to another. Mr. Bruce believes the tea-plant 
to be so liardy that it would live almost in any soil, 
if it were only planted in deep t^hadc when tsken to 
it. Tlic roots should be well watered, but not 
inundated ; when they have taken hold, tlie shade 
should be removed. Prom moderately-sized plants, 
removed from the jungle to a garden, a amall crop 
cf tea Diay be gathered next year. From plants 
raifted from seed, a erop may bo expected tlte third 
yenr ; tiicy Kach maturity in six years, and live 
forty or AAy, 



METALLOCHROMY. 

CTq the Editor } 

Sir. — In experimenting upon this subject, 1 find 
that plaliaa may be colored eimilarty to steel, by 
rmploytng a solution of sulphate of manganese. 
The colors arc even more beautiful than those pro- 
duced on sicci, but the rings are much smaller. 
TXin positive wire must slightly touch the platina 
foil. I have tried a steel plate also in the same 
ihtlution, and find that colors may be produced on 
H ui a slight degree. 

The battery made use of was i Grove's battery 
of (wo small jelly jars, 

Trusting that it may afford aome infonnatiDn to 
your readers I have troubled you with this account. 

JOHN lAVAOI. 



MISCELLANIES 

CryttnUized Omaimentt, Aitim Baskets, ^'c. — 
Dissolve 2 lbs. uf alum in a quart of hot water, 
pour it into a Jar, and iinmer«c in it one of the 
folluwinfir or any aimilar articles, and tltere let it 
remain tilt cold, when it will be found that the 
alum has been deposited upon the object immersed 
in it in the shape of (he most beautiful white 
crystals. The objects mny be either some twiga.of 
a Irre, covered loosely with worsted, or eUe a 
frame-work made of brass wire, and covered in the 
same way ; it may represent a basket, crown, 
church, or in fact any thing that the taste of the 
maker can suggest. When immersed in the alum 
water it must be wholly covered with the liquid, 
and should not touch the bottom of the vessel. It 
may be colorf d by boiling up with the alum log- 
wood or orchill, for purple. Braxil wood or re<l 



oicaH 



cabbage, for red. Turmeric or aaffrooi for aaiWi 
Gamboge or weld, for jellov. S^ gVMB 
blue, indigo, alkanet nxit, &e. Ac., A>r the 
they yield ; but if blue is dacirM, ioitead of 
use the sulphate of copper or bloc •tone. 

^^eeii of Mu$hroofn» <m t\t il Jr.— According tl 
Dr. Marict, mushrooms produce very diSanBl 
effects upon atmospheric air from thoae 
b;^ green plants under the same droomstant 
air is promptly ritiated, both by abaorbing 
to form carbonic acid, at the expesue of the 
ble carbon, or by the evolution of caibotoc 
immediately formed; the effects cppCBr to be 
same both day aod night. If frewi mnahroonu bc 
kept in un atmosphGre of pore oxygen gaa, a Urge 
proportion of it disappears in a few boors. O: 
portion combines with the carbon of the 
to form carbonic acid, and another is fixed fai 
plant, and is replaced by azotic gas disengaged 
the mushrooms. When fresh moshrooms are 
for some hours in an atmosphere of asotic gas, 
produce but little effect upon it. A small qoaatt^ 
uf carbonic acid is disengaged, and in some cam 
little azote is absorbed. — PhUot. Mag, 

Reduction of^fetal!ic Poitotu — Arttmicj. — Gobe: 
has found that formate of soda fumiahea tlie mosi 
ready meanH of reducing metallic poisona, not on)] 
when in the state of oxides, but as soiphurets. 
and is, therefore, of extreme impoftance in 
searches connected with medico-legal inquiry, 
substance to be examined is mixed with the (a 
and heated in the usual manner in a small gLaa 
tube, over the flame of a lamp ; the arsenie, if prcarw 
of course, sublimes. In this way Oobel has d*. 
tccled the presence of orpimcnt in the golden 
pburet of antimony, when present only In 
proportioa of one part to 1,000 of the an 
sulphuret.-^J'aArej — Berieht der Phff»^ W\ 
chqflen; Phiht, May, 

Mode uf yrgventing Bwr Jirvm bfcoming add.-^ 
A patent has been taken out, in America, for pro. 
serving beer from becoming add in hot weather, 
between the tentperatarea of 7<' and 94*. Ti> 
174 gallons of liquor, the patentee, Mr. S 
directs the use of 1 lb. of raisins, in the ft 
manner : — " Put the raisins into a linen or 
bag, and then put the bag containing the 
Into the liquor before fermentation ; the liqi 
then be let down at 65", or as high as 70°. 
bag containing the raisins must remain in 
until the process of fermentation has so 
vanccd as to produce a white appearance or 
all over the surface of the liquor, which will 
bably take place in about 24 hours. The bag^ 
tuning raisins must then bo taken out, an 
liquor left until fermentation ccasc». The 
of heat in the place where the working 
situated should not exceed 6G°, nor be less 
60"." To prevent distiller's wash from 
add, 2 lbs. of raiAlns should be put Into 1 
gallons of thewasli, the raisins being chopped « 
put in wtthont a hag; and 106 gMllois of hopl 
should then be put into the wash rat for erer^ 
eight bushels of malt at the time of washing^. an 
thrve- quarters of a pound of bops for every bush^ 
of malt brewed, to be boiled nn in the Uqnor in 
copper. — JoHfnal of the Franktin in*iitvt9 
America. 



UxDOv— PfiottNl lij l», raAxcis, 6, Whjtc Hone l.(Ktm, Mile End.— fuUubcU l»y VV. UaiTUiM, II, FoUzoMlu Uom* ^ 



TOE 



GAZINE OF SCIENCE, 



^nDT ^cj^ool of ^rt0« 




h »*— wo. XT, 



^u 



MAGAZINE OF SCIENCE. 



ELECTRICITY. 

f Rrmiaal /miu f^ge ii.J 

CwAY periofi mho u Bccutomed to or acqaainted 

icitii the use of an electrical macliine, is aware of 
the very great difference of appearvDoe and effect 
of a ball and a point when electrifted. The fluid 
pauca from or to a boll in a spark or cadden flash 
— from or to a point it proceeds ailently, gradually, 
rimI ia many eases imperceptibly, eren when in tbe 
gmlcst quantity, l^eini; aeen on th« point anly ttke 
a aCor, or a brush of li^bt. Also, it is well known 
Uut a {Niint aUraela the floid from a noch greater 
iliatoQDc then a ball docs — mni also in much greater 
quantity. Tfacae fteUM bvro giTm rise to very ini- 
lucrouB highly intnit iC'wg espcfimenta, and aiao 
direct tti haw to acw u nDl a ap, relmin, or dl«p«r«e tb« 
•lectrffcal fluid with tht? grentc^t facility and cct- 
tainty, at (he same time proving tbe laws by which 
the dilTerent appearances are obserred, and also 
ahowing the appltcatioti of them equally to purjioscs 
of amusement, instruction, and utittty. 

£j: 16. — Hold a sharp needle at a few inches 
■distance from a charged conductor, and try witli the 
•4>tb« hand to take a spark ; it will be found that a 
•park will not pass to the hand nnttl the needle is 
withdrawn, allliough Che needle may have been held 
•t duuble the diatance at which the spark would 
olherwiae hare flown across. This experiment 
ahuwa that during the working of a machine no 
•har|i points or edges must be any where around it, 
or they will all tend to draw off some portion of the 
fluid. So also it is requisite tliat every part of the 
electrical maebine, and moat electrical apparatus, 
must be made with well-rounded edges, and nitbout 
ludden prominences or projections of any kind. 
Every thing of this kind must be well freed from 
dust when in use, ox crcry particle is a point con- 
ducting away the duid : and not merely on the 
artictej and t«bl£ around, but still more especially 
from the wurking part of the machine Uidf, aa ti 
proved by the following. 

Br. 17- — Place a pointed wire on the prime 
conductor, turn the cylinder, oiid tuo whotu fluid 
produced will be disaipatcd by tbe point. TIim 
ffemale»» when electriHed by being placred on a glaia 
•tool, seldom give ao strong a spark as male persons, 
because of the pins in their dress, or their hair; 
the ed^ej of their garments, broachea, eir-rings, 
&c., being like ao many conducting puinta, which 
men'a drcsa ia more free from. Let it be remarked, 
hvwevcf, that points when covered up have not thia 
tendency to diwipate the fluid which chargea them. 
J£je, Ifl. — In tiie last experiment the point linTing 
been fastened to the prime or posittTC condurtor, 
gives off the fluid in the shape of a brush of light, 
as in Fig. I ; but if it be placed on tbe nrgntive 
conductor or oufthion, its chain being removed, ft 
will appear like a star, as in Kig. 2. This is seen 
olao by either of the following methods : — 

£.r. 19.~Take away the chain of the eusliJon, 
and plac« a pointed wire, a foot or more long, in a 
hole made on tbe top «f that cushion, and abo 
another timilar wire on the top of the conductor ; 
let tltt* point* of these respective wires approach to 
within A foot or less of each other, when upon 
turning the machine a bru^h of light will aj^pear 
ttjKjn the one, and « star upon the other. 

E^. 20. -^f the etuhion i>f the machine be not 
adapted fbr the purpose, hold its wire in the band 
towards tbe other wire, and tbe same appeatuoce will 
bv exhibited. 



The cause of thia la easUy explained. 
sitive wire ia giWag off the fluid, the 
receiTing it, (See Figs. 3, 4, and &.) 
passes from 3 with considerable impetne 
and aa the particlea of electric matter 
other, it doea not paas in a r^ular denae 
from 3 to 4, but divergea into a bruah. It 
vented, howerer, from diTcrging too fia i«j 
quence of the attractive power of the 
point 4, where the rays of fluid are again 
Were tber« no other force in action than 
traction on the ncgstirc aide, and repulaaon* 
positire, the arc of fltud from one to the (Klwr^ 
wonld be a|^dle*dkaped, u it ia in g«)i 
in free eta m i icity the repohioD from ths 
«Ue ia wnich gmter tfan the altnctiTC fen 
oegfltlTc aide— thns the fluid leviAig firoa 
acquires a conndenible impetus of momenluna^ 
carries it in some degree beyond the DcgatlTW 
before it enters, (as is represented by tbe 
lines S ;) hence the cause of tbe bnsh and 
of light. 

£*. 21.— i/erfrie FTi^er,— Place upon 
doctor a pointed wire, and balance upon thie 
or star of wires, every ray of which ia bent 
tbe end in the same direction, aa reper s eai 
Fig. G. The fluid issuing from tbcae rariova 
will turn the star of wirea round in the 
direction. 

Er. 22.Sman Orrtry. — Instead of the 
the lost experiment, support a small onvry,' 
OS in Fig. 7. with a single point near the ci 
jectiug sideways ; this also wiU turn nt 
exhibit the morioa of the moon round the 

£s, 2Z. ^Electric Orrery.— This aj 
seen in Fig. R. It rrpceaenta the sun, 
moon. The earth and moon are formed 
in the lost experiment; thry are balanced 
centre of gravity, upon a painted wire, 
ita other end the sun ; this wire has a point' 
Jeoting tidcwoyi near Its fartbeat estnntity. 
moon also bears a side point, thus (every 
being nicely balanced) the earth and moon 
round each other, and both together round the atm* 
making one of the best possible illustrations of 
real motions of these heavenly bodies. The 
apparatus may be six inches long ; the stin, 
be of wood. 

Kr. 2 i.— Electrical Pro#t.— Form n 
tn-o thin pieces of glass, and paste upon them 
of tin>fuil. just or nearly touching eeA othert 
witli a wire point at each end, support ^%> 
nicely, OS represented in Fig. 9. Turn the mac' 
when tbe fluid passing from the centre to 
the points will produce beautiful streams of 
conatautly in motion in consequence of tbe 
of the cross. Sole. — This cross may be 
xoolol instead of vertical. 

Rjt. 2o.— Make a windmill of card-board orl 
wood varnished, up ita centre put a wire, tbe 
end of which may flt a hole in tbe oandoecor' 
upper end must snp|>ort a needle put croi 
that its point projects through tbe bead of tfaa'] 
ready to beor tbe sails. Make the sails of 
with a fine wire running along the back 
encfa, a point of it projecting beyond tlie crtlwrl 
(See Fig. 10.) Let the centre of these sftilr^ 
small boll of metal, or else wood or prtfa gilt ; 
the sails in this ball, and [dace the whole upon 
point of tbe needle. Upon turning the maohl 
tbe mill will revolve rapidly. Thu appantttiS 



MAGAZINE OF SCIENCE. 



13 



Hilt irota one exU-cmit; to tho otUer, 
d» oUier pajU io prot)arCion. 

of flyen may be made to rtsToWe «t tbo 
if na^ rci7 Ui^it, azid delicately lap- 
aiTvijVuefit of ihu ItioJ !■ seen id Fig. 
iber of •imiUr contrivances may be 
rotuid-abouc, vach ai is leen at fiin, 
points which are to give it motion arc 
arooag these is 
■J*# BUctrieai IncUnifd Plane, — (See 
)>In vfaicta a flyer \& f^mifihed with a 
pulley at each end of an axis that 
It placed on two wires which are snp- 
Iglaa ; when this it connected with .1 
powerful machine, the flyer immediattly 

rotiad, and tr«Ter&es up the wires. 

■Rttciric Ftyer witA i(e//f.— This ap- 

irtaeoted in Fig. 13. It cousista of a 

[diflerently 'toned belli arranged upon it, 

• ^uf rod. and this supports a flyer, 

has dependent from one of its arms a 

a iLlk string bearing a brass ball, (the only 

wire is to keep the string somewhat 

Uu9 fifth arm of the flyer bearing a ball 

counterpoise for the weight of the wire 

.) To uicit, take away the conductor of 

and put the flyer in the same place ss 

■ Ot Uie coodttctor usually are, when it will 

and the ball strikidg against them, of 

belts. 

Id towards the ball of a charged 
tube (Fig. 14.) famished with a 
and contrary to the usual character 
It will take a spark ; this is owing to the 
Dilure of the conductor which connects 
the band or with tlie ground, 
pport a tpiral tube on a point, as 
ig. 15, and have a flyer aflixed to 
I) connect it with a charged prime 
when the floid passing away from the 
Cb« spiral on its axil. 



•iQ THE DECAY OF WOOD. 
b extracted from a paper read by 
of Bath, before the Society of Arts : — 
that the contact of water and air are 
CM of the decay of wood. If, there- 
can bt devised, by which the accesa 
■nd air can be prevented, the wood is 
decay. This principle may be itlus- 
'«n*i*oeing a cylinder of dry wood to be 
i cUm tube or caae, which it exactly fills. 
rnda of wLich are. as it is called, her- 
l» or entirely closed. Who will doubt 
piice of wood might remain in the open 
~ yeius unchanged ? Or let us tiike a 
lOfipotile iUuitratioti of tins fact— that of 
' to bitumen, or resin, in which a variety 
(, ftlsments of vegetables, and otliers 
fra^e substances, are seen em- 
iring be?a preserved from drciiy much 
'ggtf'^u^y* than a tfaoaiand years, and with no 
M lEwkacj to change for t«n times that 

ud moisture, Tarioos experiments 

of which the most common is 

with paint ; which is oil mixed 

capiiUe uf fiii'iug it the color 

it M wcU kfiuwn that Mveral of 



the oib, aa those of Uasocd, luuup-iced, ^c,» 
become dry when thiuly spread on any hard sub* 
stance. ThadryingquaUty is mucfatsaisled bybciac 
prarioosly boiled with certain motallic oxidot, moca 
especially that of lead, or litharge. The eraat ta 
formed is with dii&culty penetrated by moisture or 
air. For this purpoac, also, drying oil is spread on 
silk or linen, in the manufacture of DmbraUJia, 6ec 

Whcu psint is employed within doors^ it is cna* 
tomoT)' to add to the oil, besidas the coloring mutter, 
some essential oil of larpentine, which not only 
makes it dry more resdily, but, by giving it greater 
tenuity, causes it to flow more freely from the brash, 
and therefore to go farther in the work. For the 
same purpose it funns a part of the paint used on 
wood nud iron work in the open air, but most 
improperly ; for on rubbing wood piiinte<d white, 
and long exposed to the wi;atber, the white lead 
come* oH* tu a dry powder like whiting ; u if the 
vcbiclo which glued it to the wood hod been decom- 
posed and lost, leaving only the pigment behind. 

The composition, which experience lias pro\cd to 
be the best adapted for tho preservation of wood 
from both ipedea of decay, (six. the wet and dry 
rot.) is as follows : — Melt twelve ounces of ronn va, 
an iron pot or kettle ; when melted, add eight oanon 
of roll brimstone, and just when both am In a liquid 
state, pnnr in three gallons of train, or wliale nil. 
Heat the whole slowly, gradaaUy adding four ounces 
of bees' wax cut into H&all bits, frequently atir the 
mixture, and as soon as the solid ingredients aro 
dissolved, add as much Spanish brown, or red or 
ycUow ochn.\ or any other oolor. (first ground fine 
with some of the oil,) as will give the whole a deep 
shade. It will now be fit for use. Lay on thia 
paint or varnish as hot and thin as possible ; and 
some days after the first coat becomes dry, give a 
second. Those coats will preserve planks, Ate, for 
ages. Whst remains unused will become solid oi| 
cooling, and may be remclted for future occasions. 
Dr. Parry UKcd some of this compoailieci on elm- 
p&ling. which, eighteen yean after, was «s sound at 
when first put op. 

All the subslancei contained is this miilure are 
capable of perfect incorpurotinn with each other by 
heat, and when sep.irutvly expoacd, are with greet 
difficulty acted ou by nutrr or sir in any heat which 
occurs in our climate. They alunild be appbed hot 
with a couunqn painter's brush on the wood which 
is previously rery dry, so aa to sink deeply into Its 
pores ; and though at firat (bey are apporendy 
somewhat greasy whrn cold, yet after some days they 
make u firm vsruish, which does not ootDI off on 
rubbing. When it n required to give beauty to the 
work, coloring matters may either be added to the 
mixture, or afterwurds applied over it in form of 
common paint. Two coats of the compesMoa 
should always be given ; and in all cenpouid 
machinery, the separate ports should he so var- 
ntslkcd before they are pnt togethrr; sfler wbirh it 
will be pradeal Co give a tltird coating to the joinln, 
or to any other part which is peceiiarly exposed to 
the action of moisture, such as water-shoota, flood- 
gates, the beds vt carts, the lops of ftosts and rails, 
and all timber which is near or within the groood. 
Bach cost should be dry before the parts ere joined* 
or tlte lost cittit applied. 

This conipodiiiim will also prereat iron and ether 
metals from ruiititig. 

It is necessary to nnenlinn, Chat eonposHiont 
mutle of hot oil should, fur the soke of security, be 
bented in meCullic or gloicd e<ir(hen vessels, ia Ihff 




116 



MAGAZINE OF SCIENCE. 



open ftlr. For wbencrer oil ti brought to the 
boitiiv; point, or 612 deppron of Fahrenheit's tber- 
nemcurr the vmpour unmedUtel/ cotcbes firr, 
■IthDB^ not in eoatacfc with iny lUme : now tbon^ 
m lov«r d^ree of lempenture than that of boiling 
•hould bfl used in tHU prooon. it ii not alwayi 
praoCieabU either aactly to r^cvlatc the beat, or to 
prerent the orerfloinof of the materiaU ; in either 
of these caeei. were the melting perronned in a 
boun, the moat fatal aeddeota might follow. 

Pre«ervafJon of Wood by Charcoal.— Tiitt fol- 
lowing mt>de of prercnting rottenneaa in pales» 
wat«r-«boota« &«.. ia also recommended by Dr. 
Parry, who aayi :— 

** More than thirty year* ago thii fubject pre- 
eented itaelf to my mind, on seeing some water- 
abooCa, wfaidi had been pitched and painted in the 
common way, taken down in a state of complete 
rotteimeM. I bad read that charcoal barird in tbe 
moist earth, had come down to ua perfectly ftound from 
the times of the Romans ; and Uiat posts long 
withstood the same moistare, if the part intended to 
be pnC into the ground was charred all round to a 
certain depth. ImprcMed with this fact, I deter- 
mined to try an artificial coating of charcoal, and 
when new water-shoota were conjtruct4>d, 1 Htrongly 
and carefully rubbed them with a coat of drying oil, 
wbich I immediately dredged all over with ■ tliick 
layer of charcoal finely powdered, and contained in 
a moalin bag. After two ot three days, when the 
oQ was thoroughly dried, and firmly retained the 
part of the charcoal, I brushed olT what 
kioae, and over that wbich adhered 1 applied a 
coat of oommoQ lead-colored paint, and a few days 
aftor, a seoond. Tbe whole became a firm and aolid 
eniat ; after which the iboota were put in their 
pUcet, and being eiamined many years afterwards, 
appeared perfectly aouud. Any other color would 
probably hare succeeded equally well with that 
which I employed. I do not think that lamp black, 
which is a pare species of charcoal, would have 
answered the purpose of forming a thick defensive 
covering so well as the grosser charcoal which ] 
■aed. But whaterer sort of charcoal ia employed, 
it ought either to beyrefA rmadf, or htahd again in 
eloM veMelt, to a* to tsptl the waier which it 
■11 If win J attracta from the ur. It is to be observed 
here, that the practioe of pitching pales, &o., is 
both incommodious and ineffiractouB, as pitch is so 
liable to be melted by the heat of the aon." 



THB SINGLE KALEIDOSCOPE. 

ITS CONBTBOOTION AND DSB. 

In order to construct the kaleidoscope in ita most 
aimple form, we must procure two reflectors, abont 
five, six, seven, or eight inches long. These re- 
flectora may be either rectangular plates, or plates 
shaped like those represented in Fig. 1. baring their 
br(udest ends A O from one to two inches wide. 

If ^e reflectors are of glass, the newest plate 
(lau should be used, as a great deal of light ia lost 
fay eimiloying old plate glaaa, with scratches or 
imperfections upon its surfoce. The plate glass 
may be either quick -sUrered or not, or ita posterior 
•ornce may be ground, or covered with black wax, 
or Tamifh, or any thing else that reroorea ita re- 
flective power. This, however, is by no means 
absolutely necessary ; for if the eye is properly 
plaoodt the reAeetions from the posterior suilace wiU 
pearcely affect the distinctness of the picture, unless 



in very intense ligfata. If it should 
neceaiary to ettinguiah as completely aa 
extraneous light that may be thrown int 
from the posterior surface of the glais pi 
■ur&oe should be coated with a vareiah of 
refrmcttve and dispersive power aa the glaaa. 

fig. I. 





If the plates of ghua have been skitfnlly cA 
the diamond, so aa to have their edges Dcn 
straight and free from chips, two of the edpM 
be placed together, as in Fig. 1, or ooe edn « 
plate against the f»rresponding edge of ue I 
But if the edges are rough and uneven, ooe of 
may be made quite straight and free from a0 ii 
feccions. by griudii^g it upon a flat surface with 
fine emery, or with the powder scraped fr 
hone. When the two plates arc laid together* 
to form a perfect junction, tliey are then i 
placed in a bnue or any other tube, so at |0 
an angle of-l^", 3G°, 30^, or any even aliquot p 
a circle. In order to do this with perfect acci 
direct the tube containing the reflectors to aoj 
such aa M N, placed very obliquely to one i 
reflectors A O, and open or shut the platea I: 
figure of a star is formed, com|>nscd of d, ] 
12 sectors, or with 4, 5, or 6 pointa, oorreapo 
to angles of 45^ 36^. and 30^ When a] 
points of the star are equally perfect, and oi 
tbe lines which form the salient and re-Oil 
angles disunited, the reflectors must be fixed ti 
position by small arches of brass, A B, filed 
till they exactly fit the space between the opei 
of the plates. The platei must then be In 
this position by pieces or wedges of cork or 
or any other subalaiioe pushed between thea 
the tube. The j^reatest oare, however, mu 
taken that these wedges presa lightly upon t 
flectors, for a very slight force la capable of be 
and altering the figure even of very thick |^ 
gUss. 

When the reflectors arc thus placed in the 
as in Fig. 2, their extremities a E, 6 E, ne 
eye, must reach to the very end of the tube* i 
of the greatest importance that the 
u possible to the reflectors. 




The other ends of (he reflectors A O, 
must also extend to the other ntremity of tbe 
in order that they may be brought into cootao 
the objecta which are to be applied to tbe i 
meat. In using transparent objects, the cell 
contains them may be screwed into the end i 
tnbe, so as to reach the ends of the reflect 
they happen to terminate within the tube ) ll 



i 



MAGAZINE OF SCIENCE. 



r-i* 



groove* 



*lf 



thm coostnurtied is iacapable of bang 
t» «|Mqiw objnrtj, or to tniupareac objccU 
nAveied light. 
dta pUcea are luuroirer at the eye end, as in 
S, tii«> ao^ar point E ihould be a little uu 
Mm of tl»c axtj of the tube, in order that the 
Ptaiv ia Ibe centre of the brass cap next the eye 
f te brooght as near as possible to E, U^hen 
pUtBS have the nme breadth at both ends, the 
wr prnnt E will be near the lower drcumfereDce 
tf tiha tub*, as it is at O ; and in this cue it ia 
to place the eye-bole ont of the centre. »o 
« to be m Ihtle above the angular point E. This 
is leas elegant than the preceding ; bat 
thm adnntage of giving more room for the 
IvoUoQ of a featheff or a piece of tbJn wood 
vith leather, for the jmrpofte of removing 
vrluch ia constantly accumulating between 
la some instances, the plalea have 
together in sacb a manner that they mny 
oat of the tube, for lht> purpose of being 
but though this construclioii has its ad- 
jrct it reqnirea some ingenuity to replace 
-' irH with facility, and to fix tbem at the 
'Mon which a re(|nircd. One of tlie 
-iiC methods is to support the redector 
1:1 A tr^'^'ie cut out of a solid cylinder of dry woi>d 
e/ tim/1y the same diameter as the interior diatoeter 
• ' -1 tvtbe ; and aftw a slip of wood, or any other 
'<-e, is placed along the open edgca of the 
Lo keep them at the proper angle given by 
9, the whole is slipped into the tube, where 
lins firm and secure from all accident. 
tha length of the reflectors is less than the 
Aorteat distance at which the eye ia capable of 
■ring objects with perfect distinctness, it will be 
to placo at the eye at £ convex lens* 
focal length is eqnal to, or an inch or two 
than, the length of the reflectors. By this 
ma the obaerver will see with perfect distinctness 
objecia placed at the object end of the koleido- 
This lens, however, mnst be removed when 
th<? trDttrnmeat is to b« used by persons who arc 
Sbted. 

proper application of the objects at the end 
of th£ reflectors Is now the only step which is re- 
^«ircd to complrte the simple kaleidoscope. The 
»<thod of forming, selecting, and mixing the objects 
win be described hereafter. At present we shall 
vonfine our atCentioo to the TsriouH methods which 
»ay be employed in applying them to the ends of 
tfae redectors. 

Th<* first and most simple method consists in 
bringing the tube within half on inch beyond the 
«n^ of the reflectors. A plane lens, of the same 
dkasteff ■• tfae tube, is thoo pushed into the tube, 
•» •• to Couch the reflectors. The pieces of colored 
^asa being laid upon this tens, another plane leiu, 
bsvtBf its upper surface ground with fine emery, Is 
•ext placed above the glass fragments, beln^ pre- 
vmted from pressing upon them, or approaching to 
ibe first plane lens, by a ring of copper or brass ; 
tad is kept in its pUee by bumishlng down the end 
of tiie tube. The eye being placed at the other 
■id of the instrument, the observer turns the whole 
noad in his hand, and perceives an infinite variety 
d beaolifiBl fignnt tnd pattcnis, in consequence of 
tte sanowsrion of new fragments which are brought 
itfl the aperture by their own gravity, and by 
motion of the tube. In this rude state, 
the iostrument is by no meads susceptible 
«f Atferdil^ vcpr pleasing exhibitions. A very dis* 



Bgrceable effect is produced by bringing the daikest 
sectors, or those formed by the greatest number of 
rcdertions, to the upper port of the circular field ; 
and though the variety of {uittema will be very 
great, yet the instrument is limited to the same 
series of fragments, and cannot be applied to the 
numerous objects which are perpetually presenting 
themselves to oar notice. Theae erils can be re- 
moved only by adopting^ the construction diown in 
Fig. 3, in wliich the rcdectorB reach the very end of 
the tube. Upon the end of the tube A, Kig. 3, is 
placed a ring of brass, M N, which moves easily 
upon tiie tube A, and ia kept iu its phwe by a 
shoulder of brass on each side of it. 

/Tfy. 3. 




A brass cell, M K. is then made to slip tightly 
upon the moveable ring, so that when the ort! is 
turni.>d rotind by means of the milled end. at M N» 
the ring rosy move freely upon the tube. The 
fragmenta of colored glos.'*, flee, are now placed in a 
small box, or ohjwct phte, as it may be called, con- 
sisting of two glaases, one transparent and the other 
ground, kept at the distance of one-eighth or one- 
truth of an inch br a brass rim. This brasa nm 
generally consists of two pieces, which aorcw into 
one another, so that tlic object plate can be opened 
by onscrewing It. and the fragments changed at 
pleasure. This object plate is placed at the iMttom 
of the cell M N, as shown at O P, and the depth of 
the cell is such as to allow tlie side O to touch the 
end of the reflectors, when the cell is slipped upon 
the ring, ^\^len thi** is done, then Lhe instrument is 
held in one bond with the angular point E down- 
wards, (Fig. 2,) which is known by a mark on Ibe 
upper side of the tube a and b, and the cell la 
turned round with the other, so as to present dif- 
ferent fragments of the included glass before the 
aperture A O B. The tube may be directed to the 
brightest part of the sky in the day-time, or in the 
evening to a candle or an Argand lamp, so as to 
transmit the light directly through the colored 
fragments ; but it will always be found to give richer 
and more brilliant effects if the tube is directed to 
the window shutter, a little to one side of the light, 
or is held to one side of the candle — or, wbat is sdU 
better, between two candles or lamps placed as near 
each other as possible. In this way the pictve 
created by the instrument is not composed of the 
barsb tints formed by trannnitted light, hut of the 
various reflected and softened colors which are 
thrown into the tube from the sides and angles of 
the glass fragments. 

In the preceding method of applying the objects 
to the reflectors, the fragments of colored glsas arc 
introduced before the aperture, and pass across it in 
concentric circles ; ami as the fragments always 
descv^ by their own gravity, the changes in the 
pictmv, though infinite in number, constantly toko 
place ia a similar manner. This defect may be rr- 
medied, and a great degree of variety exhibited in 
the motion of the fragments, by making tfae object 
plates rectangular instead of circular, and moviog 



119 



MAGAZINE OK SCI£NC£. 



them throQgh a groove cat in the cell nt M N, ia 
the wne mtnner u is Aoac with the plctarea or 
•llden for the ma^ie laathorn and solar microscope. 
By thu means the diJOerent frafmenta that preReot 
thcmadvea to the aperture tna; bo made to paaa 
acrota it in ererj- possible direction, and rery in- 
tereating effects may be produced by a combtDation 
of the rotatory and rectilineal motiona of the object 
plate. 

When the nmple kaleidoKopc i« appl)e<I to 
Opaque objects, such aa a seal, a vratch-chain, the 
aecond's-hand of a watch, ccins, pictures, gems, 
^elU, flowers, leaTes. and petals of plants, im- 
pressiona from smIi, &c., the object, instead nf 
being held between the eye and the light, must be 
Tiewed in the same manorr as wo vicvr ohjfcU 
throogh a microscope, being always placed as near 
tfie inatrumeiit as potaible, and 90 as to allow the 
ligbt to fall freely upon the abject. The object 
pbtes, and all transparent objects, may be ricwcd 
ID this manner : but the most splendid eoLhibltion of 
Ibia kind is to Tiew minute Fragments of colored 
glaaa, and objects with opaque colors, &c., placed 
ia a flat box, the bottom of which is made of a gbi^s 
mirror. The light reflected from the mirror glass. 
smd transmitted through the trannpiireiit frngmriit^, 
ia combined with the light reflected both from Che 
transparent aud opaque fragments, and forma an 
effect of the finest kind. 

COfiUiiutai on page 13S.J 



DISCOVERY OF THE MARINER'S 
COMPASS. 

Much interest mtut for ever attach to the dis- 
covery of tliis instrument, and yet there are few 
aubjecta concerning which Ic^s la known. Foralong 
period, the honour of the invention was ascribed to 
Gioia, a pilot, or ship's captain, born at Pasttano, 
a small Tillage situated nrar Malph), or AmalA, 
about the end of the thirteenth century. Ilia 
claims, howerer, hare been disputed. According 
to some, be did not invrnt, but improve it; and 
according to others, he did ncitlicr. Much learning 
and labour have biTcn bnitowed npon the subject of 
the diftcoTirrT. It has been maintained by one class, 
lliat even the Phnpiiiiinns wpro the invrntora ; by 
another, that the Greeks and Romans had a know- 
ledge of it. Such nutions, Lowerer, ha¥e been 
completely refbted. One piuaage. neverthalMi, of 
a very remarkable chnmrter, onnirs in the work of 
Cardinal de VUty, Hiahop of Ptolemafs, in Syria. 
He went to Ftilmtine during (he fourth erunadp, 
about the year 1204 : he rttumed afterwards to 
Europe, and subsequently wtrnt bnck to (he Holy 
Land, where he wrote his work entitled " Historia 
Oricntalis," as nearly as con be determined, between 
the years 1215 and 122U. In chap, loi uf that 
work he haa this ringular pHsnage : — " The Iron 
needle, after contact with the loadstone, conatantly 
tarns to the north htar, which, as tlie nxfs of tb« 
firmament, remains immoreable, whilst the others 
jwoItc 1 and hrnce it is eatentially neces4ary to 
those narigating on the oceon." These words are 
as eipHoit as they are extraordinary ; tbey state a 
lact, and announce a use. The thing, tlierefore, 
which essentially constitutes the compass, muat hat^ 
been known long before the birth of Giola. In 
addition to this fact, there is another equally fatal 
to his clnims as Ihe original discoverer : it is now 
Wttled beyond a doubt, that the Chinese wore ac- 



quainted with the compass long heiore. the Sa- 
ropesns. It is certain that there are aUosioaa Id 
the magnetic needle in the traditionary period of 
Chinese hialory, about 2600 yean bef o«« CkriM i 
and a still more credible account of it ia found ttt 
the reign of Chingwang. of the Chow djnaalft 
before Christ 1114. AJl this, however, may b« 
granted, without in the least impairing the just 
clainu of Gioia to the gratitude of maukind. Tlia 
tmth appears to be this : the poaitioa of Gioia. in 
relation to Che compasa, wa» precisely tliat of Watt 
in relation to the steam eng'me — the element exiatssA« 
he augmented its utility. The compaai used by tlw 
marinora In iIm Mediterranean, during the twelfUi 
and thirteenth centuries, wus a very uac«rtaia sid 
unsati&faclury apparatuji. It consisted only of ft 
magnetic needle floatiug in a vase or basin by mcaiu 
of two straws or a bit of cork supporting it 00 CW 
surface of tJie water. The compass used by Um 
Arabians, in the thirteenth century, was an tostiu- 
ment of exactly the some description. Now thu 
inconrcnicnco and inefficiency of such an apparsitiiA 
are obTious ; the agitation of the ocean, and tht 
tossing of the tcmcI, might render it o^eaa in & 
moment. But Gioia placed (he magnetised neodla 
on a pirot, which permits it to turn on all todtm 
with facility. Afterwards it was attainted to a card, 
divided tuto thirty-two poiuts, called Roaede Vents; 
aud then the box containing it was sutpendcd in 
such a manner, that however the vesael mtglit b< 
tossed, it would always remain hohxontal. Tbq 
reault of an investigation participated in by men of 
various nations, and pns^easing the highest d^grre 
of competrnry, may thus be stated. The diaoormr 
of the dirfrtiTc virtue of the magnet was qmhmi 
anterior to the time of Gioia. Before that ^f"^< 
narigators, both in the Muiliterranean an 
seas, employed the msgnetic needle; but L>i 
his valuable improvcnieut in the principle of aa»* 
pension, is fully entitled to the honour of being 
considered the renl inTeotor, in Europe, of Um 
compass as it now eaists. 



ANIMALCULES. 

BY Dft. ORAKT. 

" Ov the rrcmt DiseoTrrics and History of A«W 
malcules ;*' creatures living. 10 infinitely small, tlut 
tlie mejitiouing of their size aubjecta a Icctnrer, (u 
the minds of many of his hearers, to a charge of 
inoccuracy, or, perhaps, of worse. Still is it not 
the Irs true that animated beings of marrdkiua 
minuteness exist ; that miUiuna uf animalcules Uw 
in a single drop of water ; and that these creatnta* 
are uf s coaipliralr structure, and closely allied (• 
animals of a higher class. They are various l« 
species, poaaeasing relatively oerebral ganglia, resplrw 
tory. visual, masticating organs, &(;.. aud atonacdis* 
to the number of ISO in one animalcule. TIm^ 
abound in pouU, in nvcrs, extensively in the ooeaSi 
and in all waters on the surface of the globe ; oiaa 
in watera in minea, in water- percolating rocki,. 
where no ray of light |>enctratcs. Countleoa tbo«- 
sands inhabit mud ; and dust, clouds of dvsatcatMl 
earth, contain their millions ready to resume their 
liring state. They are capable of a torpid ciistcaca 
in earth dried up by a summer sun, and bibenulsi 
froKcu Ea ice. Poisona, tf cbemioally combiatA 
with the water, destroy animalrnlea, otlwrwtse their 
particles ia any mechunical disaoluttoo are tAo favfu 
to be swallowed ; but even in the case uS cfaemival 



MAGAZINE OF SCIENCE. 



119 



tom1>tf>%tion, ftnlnulctilaB often reme after imbibing 

tj.» *Tr:>'];rr?t poiiions. These powerful a^cnU, there- 

V effect upon theg<! crcaturw, rind the 

of destruction none : but t ahuck of 

tijrcTMi iTv rjarstA their bodies And kills tticm in- 

OAtiiBfie^asly. Their tneKue ii utouoding. From 

,ir,(s Tri.lii wiiiiil, \a four dftjs, one hnndrcd and forty 

'.ioDA would have existed, sufficient to 

1 cubic fe«t of siliceoos rock. Most 

0f Ui£ »ohd skeletons of polygantric Rnimaloulra ore 

Cxiemal siliceous covers »hicii f-nvelap the entire 

tei^ ; they long resist decaf, and they exhibit the 

lenrral fonn and characters of the tpedes to which 

llbff belonged. Both marine and fresh-water ipecles 

ittiTond in the trrtiary dq>osits of all latitudes, 

fuming aloue entire strata, or occurring vith the 

imaios of other ctasses ; aod they arc obaerred 

dakr with the scales of fishes, in the substaoea of 

Am iSints, or filiccoas por|ihora of the newest 

■nmdary rocks. Their remains form rast deposits 

sad bycrs of solid stone. This wonder in some 

•ttsare ceases when merged in the general view of 

^ Trrriiry ind mitst of the aecoodary formations. 

t some instances, of more than 

- fathoms in bulk, are composed 

ir.-ir •ji kucii», Uu: skeh^tous of mollttacoas aui- 

Js. Ail the limestone of the globe is formed 

aMiiiMi bodies, ond chalk contains myriads 

myriads of cephalopoda and others. Animnl- 

, thtfu, arr, *^ before said, tlie greater portion 

liiseuus rock ; their nature has been revealed by 

aiicroseupe, and tJieir internal complicate stnic- 

futly dcrdopcd by that instrument, assisted by 

lultcace and ioKi'Uuity of experimeutent. Sub- 

cuoiidcred foriDcrty. indeed almoat to our 

0«n tiroes, mere gelatiuouif portions of v^etables or 

«Popbyte«, have been jiroved by moderate accurate 

obMrrera to be distinct animalcules. Coloring 

■lAUer, canoiufl pnt into water, was quickly con- 

vamd iato the numerous cavities or stomachs of the 

MHSaknle^ and thus their whole interior was in- 

veatiiraled* 

■^■or Ehrcnberg has published an important 

.^titled "The Infiuoria, (microscopic ani- 

jra,j "i>v ) as perfect Organiama, a Glance into the 

tJtrpCT Organic \^9 of Nature ;" with an Atlas of 

^4 colored platea. In this work, which may be 

fCBSirdad aa the aummary of Ehrenberg's reacarchea 

ftnto Ckf If\fH9orio, be arrives at valuable concluaioni 

AS Ml the geo^aphical diatiilmtion of the animat- 

r, aod wtabluhes two great natural laws : l,that 

limal organiiation is perfect in all its principal 

to the eUxemc luuit of riaion assisted by 

wmOtt powerful microscopes ; and 2, that the 

tpic animalcules exercise a very great and 

inlliirncc on inorganic nature. One of the 

drawn from the first law is the great 

itabjlity of these animalcuUM, as well aa 

bodies ia general, being ever produced by 

generation. 

Ia 1h» I^/vsoria tbemsehea, Profeuor Ehrcnberg 

kM coa&rawd or finl established many very curioua 

■y**^'***— and eelatioiu. whidi ar« highly ioterestiiig 

is ■ pbysieJogicil and other points of view, the most 

iMortant of which wc briefly enumerate : 

I. Most (probably all) microscopic animateukt 
•n Iwghir-orgaoijed animals. 2. They Cornij ac- 
eardiog to their stmcturc, two well deliaed claasea. 
3. Their Mograpbical ditfjibuCiau in the fuur ports 
fff Uie world follow« the same laws as that of other 
MJMili 4. TtHyeeaMestnuive volumes of water 

tVA IB wBWVBS 



Co be CBlOTvd 



«ay«r and ocvaaioa a pe- 



culiar phosphorescence of the sea by the light they 
develop. 5. Tbey form a peculiar sort of ItTing 
earth ; and, as forty-one thousand millions of tbem 
are often within the volume of one eulne inch, Che 
absolute number of these animalculn is certainly 
greatfr than that of all other living orvatures Lakan 
tontcther ; the aggrrgsle volume ia even likely to be 
in favor of the animalcules. G. They posae* the 
greatest power of generatiuu known witldn the 
range of organic nature ; one individual being able 
to procreat« many millions within a few hours time. 
7. The tmimalculea form indestructible earth, atones 
and rocks, by means of their uliceoua trtta : with 
an admixture of lime or soda, they may serve to 
prepare gloss ; tbey may be used for making floating 
bricks, which were known to the ancients ; they 
serve aa fliuta, as tripoU, aa ochre, for manuring 
land, and for eating, in the shape of mountain- 
meal, which fills tbe ittomach with a harmless stay. 
Tliey are sometimes injurious by killing Ash in 
pouds, in making clear water turbid, and creatlii^ 
mtaama ; but that tliey give rise to the plague, 
cholera mtrrbu9, and other pestilential diseases, has 
not been proved. 8. As far as obserration goes, the 
animalcuiet never sleep. 'J. Tliey exist as en/tuea 
In men and animals, the tptrmatazoa not being 
taken into consideration here, 10. Tiiey tbemMlvca 
are infected with Uce aa well as entocoa (irorvu) 
and, on the former^ other p^rratifes have been oft- 
Mervpd. 11. They are, in general, affected by ex- 
ternal agents much hi the same manner aa the larger 
organic beings. 12. Tlie microscopic onjmulcii/ffs 
being extremely light, they are eleraCcd by tbe 
weakest currents, and often carried into the atmo- 
sphere. 13. Those obscrrern, who think they hsTa 
seen how these minute creatures suddenly spring 
from inert matter, have altogether overlooked their 
complicated structure. 14. It luu been found pos- 
sible to refer to certain limits in organic Isws, the 
wonderful and oonstiot changes of form which socM 
of these amimaleulet present. \!i. That the orga* 
niam of ttiese mumAleuleit is oomparatively powerftUt 
ia evinced by the strength of their teeth sind apps* 
ratus of masticatioa ; they are also posseaaed or Ae 
same mental faculties as other animals. 16. The 
obaervation of these microscopic beings has led to a 
more precise definition of what constitutes an auimal, 
as distinct from plants, in making m better s»- 
quainted with the system of whi^ the latter $n 
destitute.. 



IMPROVED METHOD O? DRYING 

PLANTS. 
fin a Letter addrei*t(i to the StiiM'.J 
About five years since I sccidectally discorerod tha 
following method of drying specimens of planta, 
and not having aeen it mentioned in any work, and 
also being able to procure finer specimens of plants 
by this method than by any other 1 have seen men- 
tioned, I feci desirous of making it public for Che 
benefit of other botaoUts. The only apparatus ne- 
cessary ts half a ream or a ream of brown paper, 
aitd a quire of double-crown cap paper. I have 
found that size commonly called royal to be tho 
most usefiU size for the biown paper ; it should be 
tolerably smooth, and that of the weight uf 6S lbs* 
per ream will be the best thickness. Tbe csp paper 
should be rather loose in its texture, and not t^ra 
thick ; it may be cut into half-ahccts. and each of 
these may be folded. The plan of proceeding will 
then be this : first, lay down upon s board or tabic 



130 



MAGAZINE OF SCIENCE. 



■ qaire of the brown paper — by upon it odc of the 

folded half-thrcU of cap paper, between which the 

plant ia to be Uid out in the usunl wajr. Then 

pUoe on it haU a quire of the brown paper, and 

then another hAlf-ihe«t of cap papu" with a plant 

is it— then another half-qaire of brown, and so on 

till all the rpecimens are laid in. Finally, place the 

noDunder of the brown paper at the top of the 

Mock. Should the number of Rjierlmena reqairing 

to ba dried at one time be very ^at, it may 

perhapa be sufficient to Iny a quarter of a qntre 

between eadi ipedroen, though 1 hare never used 

less than half a quire oiywlf. The time which 

Bpedmeni will require to dry upon this plan, will of 

coarsa Tary, according to the nature of the plant 

and the dn ness of the weather ; but in genrral a 

week will be sufficient in tolerably 6ne weather. 

Tbe great advantage obCaioed by this plan appears 

to mo to be tbis : tbe bruwn paper belnx flexible in 

erery direction, exerts on equal pressure on erery 

part of tbe plant to be pressed ; while in the 

eommon way of drying plants (a board being used 

to five the principal pressare) eoosidenble force is 

eierted on the prominent and more elevated parts 

of a specimen, such u tbe stem, &c., while the 

leaves and thinner parts frequently ghrivel in many 

pUnta, the tbickwMS of the item. &c.. preventing 

an adequate pressure from being applied to them. 

This I have frequently found the cue in plants 

with a woody stem, as Diitens tripartita, Senecio 

JaeobsBa, and aquatlcui, Eupstorium cannablnum, 

&c. Indeed, till I found out tbe above method, [ 

could Dover manage to preserve a good ipecimcn 

of tiie above and many other plants. 1 have con- 

atantly used this plan for the last five years, and I 

tliink that my ipeciuieos (preserved, by it) will be 

lurpuied by few for beauty. 

W, L, KOTCCTT. 



PRINCIPLES OP CLASSIPICATION IN 
THE ANIMAL KINGDOM. 
DV PBorassoK aoas&iz. 
AtmonoH tbe principal groups of animals are im- 
pmied with such characters as to bo easily reeog> 
niaad and to admit of little doubt, yet their order 
and meoesslon have been determined by no general 
prindpla. Tbis appears from the discrepancy in 
IIm poaltiona assigned to tbem by the moat eminent 
■ylamaUsta, each of whom has aasumed, arbitrarily* 
«>■• oryaa or ivitem of organs for the basis of his 
•moffmmmt. Professor Agasaii (at the last meet- 
log W Lha Urltisb AiaociaUon], after adverting to 
Mma Oermaii iMtumllsts wlio alone have sought 
after a ganeral primiple which should be satis- 
Autory lo " philoiophic naturalists." passed in 
rmrivw the daoMiB of iho miimal kingdom, each of 
wblah, he sUted, eibiblted. in an eminent degree. 
tiM dnelopment of some one of the animal func> 
linns. WlilU^ vrrtebfate animals (with man, their 
'rjt*i <iprtvw at (hi* prratcft jHrfection in the organs 
■,,1,1. lirnte offer in the class of 
..f (be •yilem of nutrition, 
. ,.i«>ii, in Lnaecta of respiration, 
*■ , . Mtirnttim. The professor neit 

f* 'intv In what manner each aub- 

<« derlraa its peculiar cha- 
I- ment of the animal eco- 
I'-ment ia the bony 
• 'nicturc in reptiles, 
■•-■"•■ in birdi, and 



the perferlion of Ibe texiaea m m ammuti A, whld 
therefore rt'prudooad tbe dtstlngaiihing 
nnd constitute the type of vertebrate ammak. Bl 
next showed that each of the other inb-eiaaMi 
Hie higher group ia repreaented among (he aaa 
ma/ia along with iti own peculiar type. He i 
plained bis reason for the fourfold divisioa which ho 
had adopted in the sub-class, pointing oat the 
affinity which connects tbe rwmman/ia the pockf 
dermaia, the rodentia, tbe tdentatm, and the 
voroas martupialia (in none of wbiofa ia tlw 
canine tooth developed), which he ooudden M 
forming a single group ; in another he uaitaa tboaa 
choractcrixed by the preecnce of the canuu tooth ia 
its proper function (as au tnstnuDeat of outriHoOf 
not merely of defence), viz. the eonuoora and tboao 
martupialia which partake of their character, and 
tbe qua^noMMa, The cetacta form a grtnip ia 
themselves, and man another. Man ia the perioe- 
tion and type of the mammilerofu oonfonnatio«i« 



MISCELLANIES. 

Imitative War Candies. — Take equal parts of 
gum bensoin and resin mastic; put each into a 
separate vessel of gloss Or lead, add spirit of wine, 
and heat them gently tQl the resinous parts are 
dissolved. Let each of tbe solutions remain awhile 
at reat. and thr4i mix them. Before 
varnish, heat it to eighty or ninety degrees 
heit ; dip into it n candle front five to ten 
and dry it carefully. By this means, comnuM 
candles may be made to resemble wax lights. 

Frtnch Photphorie Matches. — It is well known 
that phoiphorlc matches have proved so dongeruva 
u to have been almost totally supplanted by the 
red or chlorate matches. A safer method of making 
the former has been devised by tbe Committee of 
Uealth and Safety in Paris. The recipe is as follows ; 
Put a quantity of mocilage of gum arabic into an 
earthenware vessel, and heal it to tbe temperature of 
100'^ or 125** Farenheit : to four parts of Ibts 
mucilage add one port of pboephorus ; it wUl In- 
stantly melt, and should be well stirred and weU 
mixed with the mucilage ; add chlorate of potash tpi 
powder, nitrate of potash, and a little b^toin, to 
form s soft paste ; into which dip the ends of (he 
match stinks. The moas constitutes what is called 
Jklminatmg tinder. 

Spirit from the BiTfterry,— In the prorinoe of 
Luxemburg, in Bclgiom, wine, brandy, and rinc|^ 
have been made exclusively from the fruit of the 
bilberry (vaccinium myrtilttu), a shrub not hitherto 
turned to any use. Thii discovery proraiacs to 
prove of good account in those northern regions In 
which tbe bilberry grows abundantly. 

Firft iH CAimneyff prevented. — The prindplo of 
Davey's lafoty-lamp baa been eaccessfnlly applied 
to prevent firea in chimneys, by M. Maratueh, ia 
Prance. He has found by experiments, that If 
three frames of wire-work ore placed near the base 
of the chimuey. ooe above tbe other, abont one foot 
apart, no flame will pass through them, while tbe 
draught of the chimney will not be impaired, and, 
consequently, no fires can ever happen in the 
chimney. As most of the soot lodges on the 
uppermost wire, but little on the second, and none 
on tlie third, be suggesta that with a brush applied 
once a day to the lowest or two lowermost, the 
chimney will never want sweeping. 



,i« lloiM LoM. MU« End.— PttbUsbsd by W. Bainam. 11. Palnaosltf Row 



THK 



AGAZINE OF SCIENCE, 



Wita ^tf)ooi of ^m* 



»1-XVIIL] 



•BCOND XOITION. 



[PmiCB lid. 




BEHNES SCULPTOR'S INSTRUMENT. 



XVI. 



122 



MAGAZINE OF SCIENCE. 



BEUNE8 SCVLPTOU'S INSTRUMENT. 



cx«trl ytroy ■•tte, 

■ ■ •'. Itr cut a^^ it IB 

nrldpiit wimlii ■iniil lltf drMtKn.BUit lUikt * ■ulli> icncy 

may y«( txi thken off* with a# littlr Ubor to tbe 

■utptor a* poa«l)ilR. 

Thr folUiwittr In tlir iirocv'M ftdnptisl, and the 

i»I'' f '^- "'- ^rul tiuiitU'r i« llic l>c«t io- 

> iiivcoU'U fur tbr |)urpuM of 

•<, .Ml. 

I^rat, «iipiitMfl Ihiit u br ilpslrrd to form a bust in 
nmrlflit titnllAr In • hviitx fare ; thr M.*ulpTor would 
rr(|u)n* llio indWiditnl to W iinii«trj to ifiaut him a 
iv'flitlii tittnilir^r of »itttH§9, hi tiir *in>r mutiocr u 
rail |tii)(tin)- tt*Milil. nif^<» •!" ■ ^ 'i'' in 

\t iwu, tlifi-r, li.ur or iiione, <> > ir- 

■i*^t. Till' m ul|«ttH- Jurtriv '■ ■ - t m- 

■t| III inilttllK « riit'tlil ill tiiiMKU'M rtfltwi p»|««- 
- n4 fWi< tlt*l •Mfi I t r.»i<li )<iiai 1* only mnilr, 
■ inirra) < '<u*t nlM> i) nflcr 1iiU>r 

Miti'lnix !• Mt iKi» tliui* timt Ihr 

.i . ■ ." ■ ■ mid 

1 Uiik 

• lit the nhnin 

,_ , , '1,». f.-.r twi> 

>i« I ft) ■ l^'d 

Wfl. -■■ ■'•V. 

h .1 u.t t-n. 

I K\ tii« 

l<r> mIiuU 

I liiift bits 

\V!i..ii 

I llir 



" k of 
t»r 

'*tit 

> rmivr U round, 
lIlV tO|l of the 



( ■ ' ' , . .-. 

M ii«Ui>(H lui hi« Iuulu4 |m%ri 
roMuw* f— 

TItii i'lrt^ miidvl i* niMNtrtI 
wiiml iir •liMii, Aiid I* *0 |il I 
tMim-il ii|um »lil«'l» H n--'' '■ 
rtiiiml ill All*, sn iKaI iI)< 
In iiidfr lit linvr rvci) j ' ' ' i 

lifind liy liini* Wore lilni, yri wulioiil iiunliijt th*? 
wlii>lr from It* I fntml noailioit Tlif^ l>lork oi iiuirMe 
l« iiUu nupU iijNin HitotWr foot in pii< ' ' 'tr 

HHum'r, tt Imviinf l»mi lirwii liiio i(m n, 

lI'Miiult rnli«li|i'i :it>lj Inrcrr ill dkiiM.. .. . ■..'.-. llif 

t. Mill I. hi or<ltT to itvold lltr |Mi»il>iliiy of too uiurh 

i..nr. ihd IicImk >hiI Kway — itftrr !hi» tlir VAnuii* 

. ilxotM I'lum iiiuiH W lirwn bwht wUli tlw" 

I. I, .1 ii.'.Mldrnim, mid ill onl«'r llml lliii m«y br 

«l mill I'ompU'tc ncmmoT, the »»(il|»<ur u»i-> »h 

lii&tiuniKiilnf iiiPAVuncninU— whirh iimtmnictil i^ in 
1. ■ •. itatt* trmi ; ' '■ ■ ■' *■ ■■■'■ 'lifl 

.. i.U).k, «it>l I '•'. 

t( . ,, .. ; ,.trJ ntcad. dc 

on i)h~il, 

riit>i> iiMiiiMM'iiii «r* of various kinds, Kitne uf 
cxlrrmci iliii|ilii>i(y but nil upon ll»f iMimr prinriptr 
"I wllon. MR will W n>«i]iW iiiulmtmni by the fol- 

1" ' . ut iiiVfiUrd hy 

'' And wbich ob- 

- „ .1" \r(« 

111*- Ki^un- rrprr«riil* ' 
••inriiuuiwK tl»" point. ■ 

Uuiiafrr thrui to a blot I, Uttn K i> w 

•ruu-dn-uUr ca»t iron I. ..>mihly Ui lb* 

ftt«urf wiadi <up)*orU Hm uM.iici— tb«» » •iii>thcr 




capsMe wi 



Im)4 fxauA in Uae Mne oniBaofti 

tfw blurL uf hmt^Iv, m tt«ttr 

•hii^ 6ts or •&!«-»« «B « 3 ^ 

^iw^ rwono fron l)w Mitt 

«hfA ix v» 
prevratcf) (rcRB tnmtn^ . ^-cord ^ i Ad 

at Cbe faaak, «fcaek Au trto our of d» ^sIm «« 
at I. ftr.. Bftd lAidb faoAev bavY mrr<"-yHrT,4raI aB> 
bm attacked to tbos. Tbc ' -"CnaNt 

may tkaa W aaide fens h' vMW 

prrpeodicalB', «4fiqpB,orhon*vuL«i. n u ir|i»- 
dri<-a] ferak dil m loCli «di. in «ht<4i ttc nit 
travertea, aiMl iHllA ^ miJigt anablr^ UtobeA«i 
out inurr XX kaa a c caedinc la rdnTmitrnrr, B Mi| 
held faft irti^ aijvaBrd by the ktcws A, k, 
bind the slits laf««Wr. Tht upper extretoily 
\.\\f ryhndrieai t^K B. baa a rt bndrical rarity, 
which I fSHD ftti^ tiiacfcw cmag a rotatorr 
to the cia-uUr K»b, aB^ the Iraarr cyliodnc^ tak C 
by wbieh. cogelter arttfa A* abbqar mociaiis orftf»- 
Uutu) of tbc i ^at nr cyBittval tul>e B, the lud^ 
in ennbled to take Us ^a i a l i with the oec^ f«- 
pcndicular aria snj Amtiasto a planr bfUaiAf 
model or maridr. a very deeided adrwtl^r to «^ 
tors. The ratsiory moCbiias M is ftopfcd^*^ 
etTcw. 

II IS a i:ircuUr gnAmAfA TT ' 
bo adjusted ui>od iti axis 4 1 
downwards ur upwards vithiH • ■■> x.^ > <>vu. « 
tubr \\, It ii atc^Md m ill iTiOerpiit |»oiiliow If 
arrevrfiig the cfam ddow afaUwl the ' ' 
its fixtn. 

N i*a«maIicrcyKadridBllir«le b which C 
m tin suae muaer as B do« in iti 
(' Iwitiji; Iwand tigM is its pt^icr by the not 
At <) Is a ball and sodictjoittt. fixed wbeu ne 
by Ihr screw at ^. (iifs fWrs the needK' or 
r'tpAbUlt> of motion or bring set tost., 
though tnits pOftitioQ it u a: right an. 
trIaiiKular barcuutainiD^ tbe osedle j;v...v 4^^ 
atUnhed at ri^bt angles to a stem 
ball ei, this triangolar bar cootsins s 
kreps the n>Ydlr or drill moderatdf 
pnrvoDtiog iu dropping out- Q U a 
aockct thnnnb wbif h P pas-^r 
Hird upon 1* by which the d 
drrmrd, and at ll»r sjiaie tiror 
bai-k or out of thf way of t)< 
until il bf»iiflicicntly rrduccil ; 
|Hiint R rxlriidittg to the diiLauuc 
ehrrk q, bring the prrcts« point O! 
the oriicinal model obtainrd U{Mtn tbc mai 
U tht ubjcrt of the instrauieol. 

To u«f< ihi» instrument t tuerre to tcrrw n Ur 
rftft Iron bed iitiiichrd Iu ttt« model, and m 
il tbnt iIm* point K toucbra some particular _ 
1)m- nixJc-1 'tben^x thr stop 9, Iheaots^, 1/, it. atliS 
A, A, nbMTvin^ what bolt- of the bed tbe itnd al the 
back •>'^ ^^ l^^^^ iu^*^* ^^'^^ unsCTPw 9— tnuufer thv 
Initruinnit to tbe block of marblr, tix the stud tc 
thr enai^]Kindiitg bole, having prrrioosly drawxj 
bufk P. ^crev up U so as to makr the iottrumrnt 
firm, and chip or drill away ihe marble until the 
point Rjuit toucbt-s tbe surface, when g touches Q 
II nil! be tbc pcart point soagbt Prooerd in 
nf uianttci' with sereral other points, until a 
. iK-y uf tuc«siirf«ments have bMD takm, aixl 
Liii marble bu^t will of coorw kanre been gndaaUy 
bf mit iitik* thr required likeness, making the wMa 
art of •culptur« a mere mccbanie«l operslioii. 









MAGAZINE OF SCIr:NLt;. 



ii\ 



'BR IN NATURAL PRODUCTS. 

■V M. A. TBIKL'LMN. 

of rnfi'-f- <""i"-r ia vnriotii natural 

•iX'inf to ■■ nstnited, sod to be 

doubtful; ' j _ ^ince the appearance 

C works ut M. Uwcrfftc and M. Hen-c)-, 

I taformed Uie Academy of Mfdicioo that 

lit, in the tt»urs of niau aad auuuols, amoU 

I of cupper aitd lead. 

[Bntion ha» lately been agtun raised in 

, and two did'frent opmiuud huvo bceu 

pncerniog; it. 

iKTituutd ia of opiaion that it exists in all 

Iperynschy, who haj; just publtsbed a work 

MtermCioa of brend. ihinka thot thia metal 

Cii^t in brrad ; and hi: Bays that he has not 

f trace of it in ^rain. 

|ib}ect is of thR higbo^ importance, especi- 

B it t« taken into coiutderation that sinull 

i of inlphatfl of copper have been intro* 

f some baken iatu the dough, at the time 

^ it into breadf and that invc^ti^tiona arc 

f made with the vien' of detcctiug this 

of co]iper Drifin;; from this mIF. 

Hucsuon ii of flttll greater importance in 

, where the employment of sutjihatc of 

I at the present time the subject of le^l 

bona. Although thiit salt is no longer em- 

I Prance, thnnks to the meaJtures tnbrn by 

mt, it iii no less trae that it would be use- 

icidr M frriou* Q t|U(.-iption. and thnt investi- 

r.k ,,.i.i 1.,. utitlertaken by order of the 

ti ■ ^^ hof e iiatiies would be a guaran- 

1 ^, ri-e of law to the ruulta uf their 

irnts. This measure is so much the more 

ti M. Kotcrmand is not the hnst who has 

the presence of native copper in organic 

as 1 Bhtttl allow, by suniuiing Up in few 

: eK|H-rimcuts umdr. on tliis ftubjvct, which 

irangc in the order of tbfir dates. 

CW, M. Boudct inli>nr.rd the Soci/tr de 

de Pari*, at its fiilting of the K>th uf 

that M. Vanquclin hud announced to the 

that M. Srfnteiiu hud dHL-ctrd tbepreHDCe 

: iw a grral numbiTT uf viTxctubtps. 

■(|uelin li;ul alrpjidy found lliifl metal In 

Mt, as he h;ul U54.'d a cupper %ei!&el, he at- 

to this tbu coppt:r which he detected in the 

^. M. Sarzeau published. In the Jcttmal 
a work on the prtvenoc of eopper in 
and bliMMj. 

' ir, being desirous nf RiTing 
ah, aocordiu>; to Ueniliiij, 

^,..,. .,.. t meati, publiJ'hrd in 1H21, 

—1st. thta (iulin, \ftu-i botiire it had been 
d that tht- Bahv* of wiit-AnUh-t contained 
Jiad wvLTitl timra eitrai'-tt'd tliLi metal from 
of ilitfi'nntt kinds uf paiirr: — 2nd, that 
lin. H) I plAnt, lud found rop[>rr 

4 iiio ruunncr: — 3rd, that the 

ly ul . >.[.(.. , Hi vcgt' tables, Wlongs to 
who detri-leii it in a irreat nimibcr of 
mdigenoii!! plants. Tlic followinn is the 
(yrbicb br adnptrd, and winch in puhlt^ltcd 
Mcfer. Vol. ivii. pp. Ud and 340. The 
Incinerated, and the ajthes are w.Hslied with 
Malcr, to remove the «oluhlr salts : the re- 
boiled uith hydro-chloric aciJ, the ftolutiun 



UkUog. 

U M 
1 .. 



1j utnratM with ammonia, •n m to Icstb nn'y n 
•])]|;ht exoess of acid ; it it. nttrred, nnd a pUte t,f 
iron or cine In steeped in the lirpdd, and BPS'iniA? a 
cupreous ap]>earatice, ut thr e\p!ratloii of a tiny uf 
two. 

According to tlirse HiffcrcTit rjperimeiit'j, M. 
SerTTAu thus shown the qonntities of the rop|ter 
which br hna obtnined from the andermentiotto«l 
substance* ;— 
^00 gr. of grry quinquina yielded 2 mitll^r uf Copper 

„ ,, of WnddT 2 „ 

„ ,, ofu' "^ li.'oCoffwl ,, 
„ ,, of ". "11 f'ltfTce 4 „ 

of Li'inrc t;n>iiiid.'! .... 3 ,, 
uf Wheat incincraltd 7 ,, 

of fine Flour I „ 

of Blood taken cold . . 1m 

M. Sarzcau also said th.-it he found copper in bran^ 
ten, rice, sanuin. rye, bsrley, com, and in the bvk 
of malambo. But, as be upi:ratcd on too smaU 
quantities, be could not determine in what propor- 
tions. 

This chemist concluded, from hi» eiperimenH, 
that the annual consumption nf Hour in KrutH'u 
represented 7.^UM,00U.U(m kihtgrammea of wheat, 
cuntaining 361,000,000 mitlogntmmea-of copper. 

M. Sarxean blIso snys that brnneontsini a ^reaCrr 
qoanlily of copper than wheat and flour; but hn 
was unable to aM-ertain the wheMt, on arcount of au 
accident which occurred during the operation. 

M. S. haa aubstiturcd another process fur thnt of 
Mcitisner, It consists, Xat, iu wiuthiug tlic ovhey i% 
water, in order to rrmove the soluble Halts :—2itd,iu 
treatini^ with hydrochloric* acid, in iatur4tia< the 
milntion by 4n etri'jts of aiiMiionia, and in liltcrin;; 
the liijuor : — 3rd, in precipibiting die cupper by 
pruKsiate of potaasa : — Ith, in decomiKisiiv; the 
pruiiriatG thus obtained, by the action uf heni, auiL 
in treating the residue by weak sulphuric flcld. In 
order to convert it into a sniphiitc : — ^th, iu dccum- 
posing this enlpbatc by a piece of iron, lie 9ay« 
thut it ia necessary to optraU- on one pound at 
kast. 

After giving the means by which he obtainetl 
these results, M. Sanceau sayspositivfly ; — 

" CbcmiKts, called upon to give an opinion in 
ca?es of poisoning, will thus find it necessary to 1h) 
00 their gturd, when, in examining verr hirij^quau- 
titics of onimul matter, Lbry tind only trai-es of 
copper : 1 say tracer ; for I do not think that there 
exists more than a mdltgrmame of copper in a kilo- 
gmramc nf bbod taken cold.'' 

In 1832, Pit'tro Pcrr^ti. profctsor of Chemistry 
and Pharmacy at Rome, publi&htJ a work on tho 
presence of cop|K:r in wirw. lie gave oteans of 
detecting thi:! metid, And distinguishing it wheti tc 
exibts iu it naturally, and irbrn it has been intro- 
duced into it. M. Sarxeau says thnt copper, or 
iulpliate of capper which had hern added to bread, 
may b« detected by the bIow-pi|>e. whii'b is not tlu 
case with the copper which forms a coni>tiiucut (uirt 
of com or flour. 

In 1833. M. Boutigny published awork entitlcift 
Oit M<f prtitnce ^f coppet in com tvul matttf ofbrr 
mbMtattetM. He sums up the re^ulUi of his ex[>eri- 
■firnta as follows .— 

1st, P<K)d or brulh prepared in copper vrssels, 
almost always oonLiiinii ivtpper, imtrr (ir lens, whifh 
i* a great fthjeKitin to the u*cs of thit meliti fut 
ctilinary purpise* : 



194 



MAGAZINE or SCIENCE. 



7nd. Wln«, cldnr. «ik com wmctiiDCi oontain 
rojiprr, tut only wtwn Che ground in which the 
Tilu*i, ■ppltf-trmM>andcom|i;row, containa it ; wbkb 

ma u* to affinn that Ihe [ircKenco uf copper in 

[rUbIca, (lor* uot rcault Crom the act uf vcj^ctAt um, 
but from absorption . 

3nl, The detn-tlon of copper in food and driuki, 
nb«a • nrdioo-Usal q onUon. which caaan a ne- 
o^aity ft>r fr«ah laveaticationa ; and thia ihould 
render Juries rery ctrauupect iu cues o( poiaoniiig 
by copiKT. 

In t837, M. BottCtoilaC tanonaced the prranice 
of coppar ia asttSGieai «nd coadudea by Uic faUowin^ 



-* From I 



>m thotf ftcta^ It reMltt thai ■tunhw my 
tianmUy eoBtain a wdBcicBt qiuutity of cofipar to 




of thia 

U tW MMriMlMii^K beta coSectod froai 

WtU|«. Bo wiW illiiiit arii 

Vr ih»pw<»iinwiiffl ftr>l.&nMO.*' 

M. Pfii^M*ifin|WiTO. •hick rcfcntteMiKn. 

MM actiM «r I— cko to tW copMr vhsi^ they 

ilifchh ^ W» III I I ■ hy M. g^k. TW 

Mkvl^ to «fci« hfroifo «■ llift mAmi : 

"* 4o lo m^tmm fT" "**?* * ** ?*^ *°^ 

«oMaH«4) IfcaiMcdbrll li i Vlf lo«ohy. 
N«», tW MiONa v' M».«ol». M(«i hi wiMo 




WMfc4ig>woft»w%o t^n M f t m in hB »r 



In ! ■» ■ — hi t aaiaa » 
«hM«UiiWrMnik 




wM r«io 

»iiov<i<iH > >1» o w>hifci a^ M^^dfcortoT 
to«^ TW«m4o««« WteebntaAk 

tett.*hath 



». tllNam ON Tlllt «UK!TROTTPK. 




lift 

I' I 
»•> 

ai 

■ " 

f» 

«• 

I'M- 



I laka iKla H|(fMUlHHllr «f laytnn \teforc 

U ^i.l ^.4.1, f* « bfM iMa(I of a Mtill further 

Miltatii prut'va*, of multipljring 

■ t III mf pniuplilfft, (printed 

' ' T t'outidrrrd tlic pro- 

iiiIcM wo were able 

-ii of modcU in day 

1 . woo«l engraringfl, Jkc. , 

i' poiitioti always reqoirca 

iiit on. •eenied to ael Ijounds 

'1 application, t Chrn rroorted 

I to mrmount the difficulty,— 

■ KiMiiij5 and bronaing the aar- 
li'Ia to a limited eatcnt ; thia 

Inn ktill troublflMme and e^penaiTc, 

' 'ill. the ahnrpneaa and beaaty of the 

■ r.Mrtly Injured. I hare aiaoo «- 

• ll(«e -urfacMby the uie o( plumbago 

'•«•• ■'. nifl many montha ago by Mr. Parrr 

.♦-.iwanri;. TbU lail poa^iaaea some of the 



fimlti oommon to the otbera to a greater dcfm , 

in f ome iuaUneea the deposition goes on p4uti«'uy 

I am happy, bowerer, to iofbrm jou, ] have nt 

atlupted a method which anawera completely, ob. 

vwting all these objectiona, and tearing the ru- 

face of the material to be acted on aa abarp ai k 

' wai previoiu to the operation. 

I Should I he dwirout of obUioing a copper moul 1 

I or eaat from a piece of wood, plaater, or day, «r. 

I Indeed, any noD.«actallic material. 1 proceed aa M. 

I lows :— Soppoie it ii u engnved wooden blt«rk, 

and I am deairooa of metalKsiiig it, in order tkit 

1 may be able to depoait copper on iU aarfaee, (thit 

example wiU hold good for any other material,) the 

firat operation ia to take itrong alcohol, in a uorked 

gtafa vesad, and add to It a piece of phoaphonia (a 

commoo phial corked will answer the porpose); tli« 

Tasad molt now be placed in hot water for a few 

ninntea, and occasionally shaken. By thia wmm 

ihr olcohol will take up aboat a 300th of its b^tlk of 

pfaoopbontf, and we thai obtain what I would tcmi 

•B adoohoUc solation of phoaphomi. Tie nnl 

is to procure a wee* solation of nitrate rf 

~i it in a flat dish or a aanerr ; U.r en. 

of the block must now be dipped in (his 

aad let remain for a few seeonda, to allow 

ma^ary artaon to draw H Into the vowh 

nsepafstion being perfonned. a srmill portinn 
«r the akohotic •ohttioo of phoaphoms must now 
W VHHii la a oapfolc or watcb.glaas, and this 
a sand-bath, that H may be saflVrvd to 
TW block mnst now be held whh its 
....^ o«ar tbe vapour, and m immuiimie chanK" 
takea alaae; the werata of dber beooiBca deoxidized. 
md ffm place M a mei^Ok phoapheret of silver. 
vWcfc alhiBi the voltaic dapoat to gici oo with as 
— Ai i y l ^ i fj u>d ocrtaiaty aa the porart ailTcr or 

^Si atela proeeaa aaj he perfbnaed zn a few 

mA vith ahaolal* asftikty of aoeoesa. 

iar or csttfftar sarfhes af a pliaicr or day 

of a atalaa, m maaar what aha, may beliuu 

aMCaKant «Wi cqaal fheOi^. For the prooeaa of 

1 1 1* hH > «ad ahpald tha Mlerial to be noted 
aoc ha vary krge. I prefer famailag- It to the top 
■ hdl glaaa receiTer with a hit of pbeh or e«n< 
•Ml tfcw plMnr it otvr iha email oa the 
halhs the phoapboric rapov b hy thia i 
c<|«aU7 diAiaed. aad not iliaipaHj, JU «th 
solution of pbosphoms alao BM««a ; mA a aolntion 
of either of the chlorides of gaU or plakiaiuii may 
t>e uwd. 1 am inclined to tM^fc^ H^ pcvea- ^■'- 
pradenC i^ its naea in galvaaie ansiptlilliiii 
appUcabIa to other branches af art. I woaM 
commend those curious of teatii^ ib efffrts, 
a small and abarp plaster of hria Medallwa 
lU mrface in a weak eolation of afilrala of 
and take it out iwrnetU^ttly, fasten it to the 
of a gUsa tumbler, and at the same time ban a 
little hot sand ready ia a dish ; lay the watch glaaa 
containing a few drops of the phosphoric aokNkiB 
on it; now place the mouth of the tunbler orar all, 
and the medallion wUI be obserred nlmoat hutantly 
to change color. The operatioo is bow completed. 
A piece of pottery ware in the state of bisenit 
be acted on in a simiUr manner. 



amy ha, 



Uvcrpaol. Job* tt, 



TUOMAO spcwcam. 







A MUD APPARATUS FOR STEAM 

BOILERS. 

7\i the Editor. 

Ea.— The folkmin^ appBratus fau been ■aooenftiBy 

«ith ft stcftm bcnlcr, which hitherto cnllected 

Bul other wdimmt from the water, so rapidly 

M tn cnmjicl the proprirtdi to have it deuutd at 

Inwi rwire a yrar. Thb inoonvcnienoe loggcstcil 

tk bUowing appontas, which hua been used for the 

monUis with the jpratest satis&ction to 

ivTCOtor. A day or twubaok wbf^ tb« man-bole 

■■■ rcmcred, the boiler wns found as perfectly 

and fm from mad and oil other kiad of Mdi- 

■■ when &nt put up. 



A rcj)iT»'nta a hopper placed within the boiler 
•botti tu lochea below the lurface of the water, 
wkitit b thovn in the above diagram by the dotted 
bnca* 11 is an iron pipe screwed on the lower end of 
ttw borper. C a cock which ii likewiao firmly 
•wwad on the other end of the pipe, the a>ok 
Iwaing mother pipe D. on its oppocite cad extending 
4 u a ni to the a«h-ptt E. 

WKcB the water boils the mud is thrown upwards 
hj lh« force of eboUitioa, and as it desoeodi tgixn 
w^ ita own {rarity a part of it is caught — nocording 
ID the IB* of the hopper, viz : — if the hopper is 
I.IOth the sue of the bciilcr, LlOth of the mud 
■U be caught an<L there remain, perfectly etill and 
^aid tin tiici-ock C in curried, wbt^n ibeetutic force 
qf Ihe aleaia above, presaug on the contents of the 
hsp p i r the whole wUl be discharged into the at«h> 
■ii Ibis ooght to be done at least three times a 
mf, iiouuK. 

^/efs.-— The pipe wed should not be leas than an 
Inch in the bore. 



ASSAYING OP METALLIC ORES. 

""""tK metallic ores are worked opon in the large 

will be necessary to inquire what sort of 

. lud what portion of It, is to be found in a 

■ktrrmtncd qoanbty of the ore; to discover whether 

U Hill be worth vbilc; to extract it largely, and in 




what manner the prooess u to be condacted, ao as 
to answer tluit purjmso. The knowledge requisite 
for this, is called the art of assaying* 

Amuf ^ Orea in the Dry Way. — The atiaying 
«f ores nsy be performed either in the dry or moist 
way; the Artt ia the most ancient, and, in many 
respeots, the moet advantageoas, and consequently 
stili continues to be mostly used. 

Assays are made either in cnicihles with the blast 
of the bellows, or in teats under a muffle. 

AMstty WtiffhU. — The assay weights are always 
imaginary, sometimes an ounce reprcflcnts an hun- 
dred weight on the Large scale, and is aubdlvided 
into the same number of parts, as that hundred 
weight is in the grest ; so that the contents of the 
ore obtained by the assay, shall accurately determine 
by such relative proportion, the quantity to be ex- 
pected from any weight of the ore on a larger scale. 

Roojtting the Ore.— la the lotting of the ores, 
care should be taken to have small portions from 
different specimens, which should be pulverized, and 
well miAed in sn iron or brass murtar. The proper 
quantity of the ore is now taken, and if it contain 
either sulphur or arsenic, it is put into a crucible or 
test, snd exposed to a moderate degree of heat, till 
no TBpour arises from It ; to assist this volatiiiza- 
tion, some add a small quantity of jiowdcred char- 
coal. 

Fluxet — ^To assist the fusion of the ores, and to 
convert the extraneous matters connected with them 
into scoria, assayers use different kinds of fluxes. 
The most usual and efficacious materials for the 
composition of these are, borax, tartar, nitre, aid- 
ammoniac, common salt, glass, Ouor-spar, eharcoal 
powder, pitch, lime, litharge, &c., in different pro- 
portions. 

(Vwrfe <if White /7iu-.— This consisU of 1 i»art 
of nitre, and 2 of tartar, well mixed together. 

Black Flus, — The above crude flux detonates by 
means of kindled charcoal, aad if the detonation 
be effected in a mortar slightly coTered. the smoke 
that rises unites with the aikaltaed nitre and the 
tartar, and renders It black. 

ComUh Bedttcing Fhar, 
10 01. of tartar, 

3 ov. and 6 drachms of nitre, and 
3 oz. and one drachm of borax. — Mixt well 
together, 

Comith Refinmg Flux. — Deftagrate, end alter- 
wards pulrcrixe, 2 pertt of ollre, md 1 part of 
tartar. 

The above fluxes answer the purpose very well, 
provided the ores be deprived of all their sulphur ; 
or, if they contain much earthy mattera, bcoauae, 
in the latter case, they unite with ihem, and convert 
them into a thJn glass : but if sny quantity of sul- 
phur remain, these fluxes unite with it, and form a 
liver of sulphur, which has the power of destroying 
a portion of all the metals ; consequently, the assay 
under such circumstances must be very inaccurate. 
The principal difficulty in assaying appears to be in 
the appropriation of the proper fluxes to each par- 
ticolar ore, and it Likewise appears, that such a 
discriminating knowledge can only be arquired from 
an extensive practice, or ^m a knowledge of the 
chemical affinities and actions of diffe'Ynt bodies 
Dpon eaeh other. 

In assaying, we are at liberty to use the most ex- 
pensive materials to eflect our parpoie, hence, the 
use of different saline fluxes ; but in Che working st 
targe, such ejcpcnstve means cannot be applied , as 
by such procobscs the inferior met^ils would be too 



\u 



MAGAZIMK OF SCIENCE. 



• 



2ikl, Wine, cid^r, anc corn sometuoe* cootjiia 
copper, but onlj whetx the ground in whtch the 
vioci, mppU)-tmes,uid cam grow, contoinx it; whkh 
■Uows xa to affim thiit tbe presence of coppur in 
Tdgetablet, does Dot renUt from the utof vcgrultuu, 
but from ab«orptioa. 

3rd, Tbe detection of copper in food Bod drinki, 
raijea n medico-legml question, which causr-s a ne- 
ceanty for freah investigations ; and this should 
render juries very cin-'unispcct iu catei of poisouing 
b/ copper. 

In 1H37, M. BonchKrdat vinoaacrd the prenence 
of copper in mwtcies, and concludes by the follonring 
passage: — 

" From these fitcts, it results (hat muscles may 
naturally contain a sufficient quantity of copper to 
produce poisoning. 

** M. Bouehardat refers the presence of this 
copper to the muscles having been collected frum 
the stieathing of ships. He says he ofatoinfd this 
metal by the prooeu recommended by M. Sarzeou." 

M. Bouchardat's opinion, which refers the poison, 
ous action of muscles to the copper which they 
runtain. has been contested by M. OrflU. The 
fuUowiug is what he nyi on this subject : 

" As to cupreous preparstioni, bow can their 
introduction into the bodies of these rooUasrK be 
ronceived? Doubtlt>K5, sfler their solution in water, 
Now, tbe analysis of sea-water, made in various 
places, b&s never demonstrated the cxi^^tence of an 
ntum of copper ; besides, would not these animals 
be killed by swalloi^'ing a cupreous prrjMrotion :" 

From what we haVe above expUined, it would 
srem that tiie ekiscencc of copper in the native state 
]n vfirioQs substances is well demonstrated : we also 
think that the rectrnt publications of M. Orfila may 
permit gn*Ater rapidity of oprration, by trestiog 
llour or bread with pure nitric acid, obtaining a 
nitric carbtfn, treating it with disMltcil water, filter. 
ing, passing a current of hydro-sulphuric acid 
through the filtered liquor, collrctiiig llic prccipttite, 
converting it into a sulphate and u*tng the sheet of 
iron. The carbon may be incinerated in order to 
ascertain whrther any copper remaius in it, which 
ia not probable. 



BtR. SPENCER ON THE ELECTROTYPE. 
(Prom Me Atktn*um.J 

Sir. — I take this opportunity of laying l>efare 
yourself and readers a brief detail of a still further 
improvement of my voltaic process, of multiplying 
works of art in metal. In my pamphlet, (printed 
last September), 1 stated that I coosiden^d the pro- 
cess comparatively incomplete, unless we were able 
tu apply it to the multiplication of modeU in cUy 
or wood, castings In plaster, wood engravings, &c., 
■I tbe fact, that galvanic deposition always requires 
a metallic surface to act on, seemed to set bouniis 
to these brooches of its application. 1 then resorted 
to various expedients to surmount the difficulty, — 
among others, that of gilding and bronaing the sar- 
faces of such materials to a hmited extent ; this 
was aucccsaful, but still troublesome and expensive, 
and. more than all, the sharpness and bcan^ of the 
uriipnal was nectsnarily injured. 1 have since at- 
tempted to metallize surfaces by the use of plumbago, 
(sugi^rvted to me msny months ago by Mr. Parry, 
of MancJicsterJ. This last posscasett iomc of Che 



fiiulls common to the others in a greater decree, ojitl 
in ^ome instaoees the deposition goes on partially. 

1 am happy, however, to inform yon, 1 have now 
adopted a method whtch answers completely, ob- 
viating all these objections, and leaving the nir- 
facc of the material to be actcvl on aa oharp m It 
was previoQs to the operation. 

Sliould I be drsirous of ubtAining a copper mouhl 
or cast from a piece of wood, pUiter, or day, m, 
indeed, any oon-raetollic material, I proceed as fo(> 
lows : — Suppose it is an engraved wooden bluck, 
and I am desirous of metallizing it, in order that 
I may be able to deposit copper on its surface, f thl« 
example will hold good for any other material.) the 
first operation is to uke strong alcohol, in a corked 
glass vessel, and add to it a piece of phosphnntt (t 
common phial corked will answer the purpose); tlie 
vessel must now be placed in hot water for a frm 
minutes, and occasionally shaken. By this meani 
thf alcohol will take np abont a 300th of its bulk ol 
jihosphoms. and we thos obtain what 1 would term 
an alcoholic solution of phosphorus. The next 
operation is to procure a vtak solution of nitrate nf 
silver, place it in a flat dish or a saucer \ the en- 
graved face of tbe block must now be dipped in thii 
solution, and let remain for a few seconds, to allow 
capMlary action to draw it into the wood. 

This operation being performed, a small portion 
of the olcolioUc solution of phosphorus must now 
be poured in a eapsulc or watch-glass, and thi* 
placed on a sand-bath, that it may be rtiiT 
evaporate. The block must now be hcl-^ 
surface over the vapour, and an immetiiaU ..imM^r 
takea place; the nitrate of silver beoomea deoxidravd, 
and givea place to a metaHie photphoret of silver, 
which allowa the voltaic deposit to go OH with ai 
much rapidity and certainty as the purest ailfw or 
copper. 

The whole process may be performed in a fnv 
minntes. and vrith absolute certainty of xurceiwi. 
The iulcrior or exterior surface of a plaster or day 
mould of a statue, no matter what size* may be thoa 
mctallued with equal facility. For ^ prooMa of 
vaporizing, and should the materia] to be acted on 
not be very large, I prefer fastening it to Che top of 
a bell gloss receiver with a bit of pittA or cement, 
and thus placing it nttr the capanle on the sand 
bath : the phosphoric raponr Is by thia meaai 
equally diffused, and not dissipated. An ethereal 
solution of phosphorus also answers ; and a solutiun 
of either of the chlorides of gold or platinum may 
be used. I am inclined to think this process, Inde- 
pendent of its uses in galvanic precipitation, may be 
applicable to other branches of art. I would re- 
commend those curious of testing its effects, to try 
a small and sharp plaster of Paris medallion : dip 
its turfaee in a weak solution of nitrate of silter 
and take it out immediately, fasten it to the bottom 
of a gloss tumbler, and at the same time ban a 
little hot sand ready in a diah ; lay the watch glass 
containing a few drops of the phosphoric solution 
on it ; now place the mouth of the tumbler over all, 
and tlie medallion will be observed almost instantly 
to change color. The operation is now completed. 
A piece of pottery ware in the state of biacoit nay 
bo acted on in a aimilar manner. 



Liverpool. June :rt. 



TUOMaa SPIItCKB. 



MAGAZINE OK SCIENCE. 



1S5 



A MUD APPARATUS FOR STEAM 
BOILERS. 

TV /Ar Editor. 

$1^, — 7W folUrwuiK oppiuTAtiu has been uncoefiMly 
tmd vith A 9t««m boiltr, which hitherto collected 
nd otbrr sediment from the water, k> rapidly 
Id oooipd the proprietoi to buve it cleaned at 
ioe a year. Thu incoavmienee suggested 
lb» feUowfaif apparatus, which haa been luwd for the 
Ivt Qiae monttui with the jprateat ntisfaction to 
te iavntor. A day or two back whim the man-hole 
^laite was rcmored. the: Imilerwaa found as perfect) j 
dBHi mkI frt« from mud and all other ftlud of »edi- 
I when first put up. 




A represents a hopper placed within (be boiler 
MX iocbea below the Rorlace of the water, 
is shown in tlic above diagracn by the dotted 
B is in iron pipe screwed on the lower end of 
Ckc hopper. C a cock which is likewise firmly 
•crnred ou the other end of the pipe, the cock 
karinc another pipe D, on its opposite end extending 
4own to the aib-pit G. 

Whea the water boils the mad is thrown upwards 
fciy the fonie of ebullition, ond as it descends again 
ty its own gravity a port of it is caught — according 
to the size of ihe hopper, viz : — if the hopper is 
l.lOUi the size of the boiler, 1-lOtb of the mud 
«iU be caught and there reoiAin, perfectly still and 
qaict tall the cock C is turned, when the elastic force 
«f tJbtt kteuQ ab<ne« preaai^g on the contents of the 
kvpper the whole wUl be discharged into the a«h- 
yil rhis ought to bo done At least tlireo times a 

4sy. UOMUB. 

V .- — The pipe used should not be less than an 
. Lhe bore. 



ASSAYING OF METALLIC ORES. 

Bvroaa metallic ores are worked upon in the large 
wiy. It win be necessary to inquire what sort of 
vetal, and what portion of it, is to be found In a 
dacenniocd quantity of the ore; to discover whether 
h will be worth whilo to extract it lazgely, and in 



what manner the pniceis is to be conducted, so as 
to answer that purpose. The knowledge requisite 
for this, is called the art of aasajtog. 

Aaaj/ qf Ore§ m the Dry Jfay.— -The assaying 
of ores may be performed either in the dry or moist 
way ; the Arst is the moat ancient, and, in many 
respects, the most advantageous, and consequeutly 
stiU continues to be mostly uied. 

Assajre uv made either in crudblet with the blaat 
of the bellows, or in teats under a muffle. 

AtW}/ Wtighta. — The assay veighta are alwayi 
imaginary, sometimes an ounce represents an hun- 
dred weight on the lai^e scale, and is subdirided 
into the same number of parts, as that hundred 
weif;ht is in the grest ; so that the contents of the 
ore obtaioed by the assay, shall accurately delermioa 
by such rejativi; proportion, the quantity to be ex- 
pected from any weight of the ore on a larger scale. 

Rwuimg ike Ore, — In the lotting of the ores, 
care should be taken to have small portions from 
different specimens, which should be pulverized, and 
well mixed in an iron or brass niortar. The proper 
qonntity of the ore is now tnlten, and if it contain 
either sulphur or arsenic, it is put Into a crucible or 
test, and exposed to a moderate degree of heat, till 
no vapour arises from it; to assist this TolatUixa- 
tion, some add a small quantity ot powdered char- 
coal. 

Fiuxt* — To assist the fusion of the ores, and to 
convert the extraneous matters connected with them 
into scoria, assayers use different kinds of fluxes. 
The moat usual and efficacious materials for the 
composition of these are, borax, tartar, nitre, sal- 
ammoniac, common salt, glass, fluor-spar, charcoal 
powder, pitch, lime, litharge, &c., In diflVrent pro- 
portioiuL 

Cntde qf White fTajr-^This ooDsisU of I part 
of nitre, and 2 of tartar, well mixed together. 

Black Fiujr, — The above crude flux detonates by 
means of kindled charcoal, and if Che detonation 
be effected in a mortar slightly covered, the amoke 
that rises unites with the alkalised nitre and the 
tartar, and renders it black. 

CorruMh Seducing Hiw. 
XO 01. of tartar, 
3 ox. and G drachms of nitre, and 
3 ox. and one drachm of borax. — Mist well 
together. 

CbrnisA Refining Fhix. — Deflagrotei and after- 
wards pulTcrixe, 2 parts of nitre, and 1 part of 
tartar. 

The above fluxes answer the purpose very well, 
provided the ores be deprived of all their sulphur ; 
or, if they contain much earthy matters, because, 
in the latter case, they unite with them, and convert 
them into a thin glass : but if any quantity of sul- 

ghur remain, these fluxes unite with it, and form a 
ver of sulphur, which has the power of destroying 
a portion of all the metals i ooitfeqiwiitly* the enay 
under such circmnstanocs must be very itiaocurat«. 
The principal difficulty in assaying appears to be in 
the appropriation of the proper fluxes to each par- 
ticular ore, and it likewise appears, that such a 
discriminating knowledge can only be acquired from 
an extensive jiractice, or 0*001 a knowledge of the 
chemical affinities and sctions of dilfe-ent bodies 
upon each other. 

In assaying, we are at liberty to use the most ex- 
pensire msterials to effect our purpose, hence, Uie 
use of difTerent saline fluxes ; but in the working at 
large, such expensive means cannot be applied i as 
by such processes the inferior sictals would be too 



i 



19C 



MAGAZINE OF SCIENCE. 



much enhanced in vftlur, especi&ll; in working rery 
poor orcf. In consrqncnrr of winnh, in smrtltiaK 
workft, where tbe object Is tlic production of mrUla 
in the great way, cheaper ailditions are used; audi oa 
lime-stone, feld-spar, flour-^par. qitartx. sand, 
i\nte, and flags. These >rr to br chosen ftcrr^rdiag 
to the dilferenC vtewi of tbr operator, and the 
luture of the ores. Thui iron ore«, on account of 
the argillaceous earth thej contain, re(]atr« calcare- 
ou§ ndditiona, and tbe copper ores, ratlier ili^ or 
vitresccnt stones, than cakareous earth. 

/fumid AsMay nf Mtiaiiic Orrn. — The mode of 
afSAyiiig or«8 for Uieir particular metals by the dry 
wuy, i« deficient «o far as reUlea to pointing out 
the different snbatances connected with tluim, be- 
can&c they are always destroyed by the process for 
ohctiiiiinE; the assay metal. The usstiy by the mowt 
way is njore correct, becaase the different substances 
ran br anMinilely AACfrtained. The Inte celebratod 
Bergmun tirst communicnted this method. Il de- 
pends upon a knowledge of the chemical affinities 
of different bodice for each other ; and roust be 
vnrtcd according to the nature of the ore ; it is very 
exten&ivc in iL<t fipplication, and requires great 
patience and addreio in its execution. To df»crib« 
till) treatment of each variety of metallic ores, 
would take up too much of our room ; but to gire 
a general idea, we shall describe tbe procedure, 
both in tlie dry and the humid way, on one species 
of all the different ores. 

To Ansatf Jrmt Oret. No. 1. — ^Hw ore most be 
roasted till the vapoar ceases to oriw. Take 2 assay 
quintals of it, and triturate them with one of fluor- 
spar, I of a quintal of powdered charcoal, and 
4 quintals of decrepitated sea salt ; this mixture ia 
to he put into a micible, lined on the inside with 
rlay and powdered chareool ; a cover must be luted 
upnn the crucible, and the crucible itself exposed to 
■ violent fire for an hour, and when it is cool, 
broken. When, if the operation han been well 
conducted, the iron well he found at the bottom uf 
tbe cnicihle ; to which mu.<it be added tho?:r metallic 
parficlcs, which may adhere to the scoria. The 
mt'tnllic partii:les so adhering mny be .«rparatcd, by 
pulveri/ini( it in paper, and then attracting them 
with a magnet. 

Nu. 2. — If the ore should be in a colciform state, 
mixed with earths, the roasting of it prrTioua to 
n^Miying, if not detrimental, is at leapt superfluous ; 
if the earths ^hollld be of the argillaceous and sili- 
ceous kind, to half a qnintol of them, add of dry 
quick lime and fluor-spar of each I quint&l and ^, 
reduced to powder, and mix them witl» ^ of o quin- 
tal of powdered charcoal, covering the whole with 
one ounce of derrrpitated eomraon salt ; and ex|KH(e 
the luted crucible to a strong forge firr for an hour 
and a quarter, then let it gradually ooolt and let the 
rcgulus be struck off and wnghed. 

No. 3.— If the ore contain calcareous earth, there 
will be no occasion to ifdd quick lime ; the propor- 
tion of the ingrt-dieuts may be as follows :— viz. 
1 a.s5ay quintal of the ore ; 1 of d^repitated sea- 
salt ; i of powdered charcoal ; and 1 of fluor-spar, 
and the process conducted as above. 

There i* a great difference in the regnli of iron ; 
when tbe cold rcgulus ir stmrk with a hammer and 
breaks, the iron is called cold frhorl : if it break on 
being struck red-hot, it is culled red short , but if 
il resist the hnmrnci, both iu il* cuid and ignited 
state, it i^ good iron. 



HMmid AwtOf qf Iron Ore, — To assay the cUrt^ 
form orcf, which do not contain much carttir •> 
»tony matter, they must be reduced to a tint- po« di'^. 
uud dissolved in the marine acid, and prectpiuiv^t 
by the Prussian alkali. A determinate quantity of 
the Pmsiiau alkali must be tried previooslT, to as- 
certain tbe portion of iron which it will )>recipLlalrr 
and tbe estimate made accordingly. If the mm 
contain any considerable portion of nine ur manga- 
nese, the precipitate mnst be calcined to redocofc 
and tbe calx treated with diluted nitrooa uU, 
which will then take up only the oxide of aioC; 
wheu this is separated, the calx should ogoio bt 
treated either with nitrou« acid, with the ■<)•)< i-"n ••/ 
sugar, or with the acetous acid, whii:b w>L' 
the ronnganese, if any ; the remainini: oxi>: 
mny then be dissolved by the marine ncid, 
cipiuted by tbe mineral alkali ; or it maj t 
cntctned, and tlien wei^rfied. 

Zine Om, — Take the assay weight of ivastaj 
ore, and mix it well with ^ part uf charcoal dasta 
put it into a strong luted earthen retort, to which 
must be fitted a receiver : place the retort in a for. 
nace, and raise the fire, and continue it in a violrul 
heat for two hourfi, suffer it then to cool gradually, 
nnd the ziuc will be found adhering to the neck of 
the retort in its iprtallic: form. 

In the hwmid tray. — Di»til vitriolic nr' ' 
calamine to dryness ; the residuum must be 

in hot water j what remoina undissolved is .; 

earth ; (o tlie solution add caustic volatile olkoii, 
which prr^pitatrs tlic iron and argil, hat keeps the 
line in solution. The precipitate must be re- 
difsnlved in vitriolic acid, and tbe iron and argd 
separated. 

'An Orvs. — Mix a quintal of tin ore, preTioaaly 

washed, puh-crizcd, and roasted, til' —^ "• ' 

vapour arises, with half a quintal of > 

and the same quantity of pnlrerizcd y. 

to be put into a crucible moiitlened mth charfro*!- 

duKt sad water, and the crucible placed in nn ntr 

furnace. After the pitch ia burnt, givr i 

beat for a quarter of an hour, and on wi'.:. 

the crucible, the regnlua will be foujid at the vk-jhii. 

If the ore be not well washed from earthy inattera, 

a Urge quantity of borox will he rrctuifite. witk 

some powdered glass ; and if the ore oontaia JitMi) 

some olkaline salt may he added. 

In the humid trny. — The assay nf tin ores in the 
liquid way, was looked upon as impracticable, till 
Bergman devised the following method, which is 
generally successful. I^t the tin ore be well jtejia- 
rated from its stony matrix, ,by well washing, and 
then reduced to the mO!«t subtle powder ; digc*! H 
in coneentrated oil of vitriol, in a strong heat for 
Meverat hours, then, when cooled, add a small portion 
of concentrated marine arid, and suffer it to etamd 
for an hour or two ; then add water, and when the 
solution is clenr, pour it off, and precipitate it be 
Axed alkali — 131 grains of thifi precipitate, w«ll 
wu»lied nnd dried, are equivalent to 100 uf tin in it* 
regulini^ state, if the precipitate consist nf pure tin ; 
but if it contain copper or iron, it must be calciiMld 
in a red heat for on hour, and thfn digested ia. 
nitrous acid, which will take up the copper ; and 
af^irwards in marine acid, which will separate the 
iron. 

Suir. — llie numai of tLiP sriiU h.c, in ilili )><i|**'r. 9t» fiur> 
poMly jlvt'ii IU known Iu tli« Uiiicr fiilliCT Uian Ui<- CitcniiM. 

(To be con/*w$ed.J 



MAGAZINE OF SCIENCE. 



127 



COLORING INSECTS. 

■ T M. J. J. VIRKV. 



the dtscorery of the M^jciciia cocfaine*! 
cdc/i trovcineltifrri) t the aucicDtit knuw bow 
rAtatn ft purple djr, Dot only from the univalve 
[ti I'nI mnrex, baC alio from sevt^nd in* 

pit dye iti spoken of tu the Bible; and 
I'linc tfndrf to convince iu thai it was not 
td (at least uot entirely) from the kermes, or 
iUciit. but from a cochineal procured firom 
iraiatia ftiid Fer«ia, formerly known to triveUen 
Mcrciiatiti by the name of tur/imr, Tht.s term 
iftea a little red worm, tike our word vermillion, 
tike the word ftcvlct (or aeharlaih of the Ger- 
l) flomci from kfrmctinas, &c. 

oochhkCftJ was not well known to naturalists, 

the publication of tlie recent Memoir of M. 

BrvoUl. It abounds in Erivan, and the valleys of 

\r«r«t ; partj uf Pcrhia ami Armrnia, now incnr- 

pmtnitti with the empire of Russia. It is parti- 

wn\**if romittnn in the swampy mctulons surrounding 

' -I and fixei on the root of the Poa Funtfent^ 

^irfurojuu L^vl» of Trinius. 

'••i-nt. tUcrefore. tli»t iu habits resemble 

''ocrut Pofimiciit, described byBreyn, 

-n the *e/era«/AfMr pfrninui : but the 

hineal is much thicker than the Polish : 

■ ut from IH to 23 thousand individuals 

'1 300 p^ammes, or ■ pound (of 12 ounocii), 

c poquire* 100, and sometimes 130 thousand 

1^ uic Coccus PatonicuM, for the same weight. 

txichineut runs 'JO to 25 thousand to thh 

therefore it presents scarcely as much 

colorinf mattar u the Armenian ; bat the Polish 

^«r« the Icaat (it is the Porphyrophora FriMchii.) 

Sje££tr^t\z to Brandt. Armenian cochineal (por- 

pAjfr^^k. J/amfUi) is distinguished by thirteen or 

fomrirmtk articulutiont to eai*h nnteiina, in the male, 

■od a bnub of the hair at tlie anus. The fomale, 

the sitstc of lana, lives in a shell attached to the 

d the plant : it can dig the. ground wiili itit 

pews. When perfect, the month is entirely 

AS in the Polish kermes ; for these aol- 

of the ume genus, althooj^b they are of 

rrrml tpeciea. 

We Boaj also mention, among tinctorial insects, 
<hr /^y:..">.i-^■.iw '*>irtorium Fahr. {acani* tinct, of 
Luib* common in hot ctiDiates, as in 

Vnrtr I mar. according to Caillaud, and 

|Mrt..cuUrlv iu iiuinra, where it has be^un to be 
t^^t*" n**" *t( in dyeing. 

, very amall red acarus, like our 

■ly numerous in the woods and 

> W..M, Farsgiiar. and French Guiana, 

ol ctflor raiifht also be extnicted from 

•jt for the ineupportable itching which 

1 on thcskin. However, the vapourof 

s them to perish easily. 

if^iil butterflies, or the coleoptera which 

lo pre*er\e uninjured for collections, 

.t!.. ^ iiiinl by put(i(ii.'-a drop uf acetate of strych- 

iisiu cither the trunJe or the month. The insect 

bOt mo«ionles« wiUionC spoiling Its shape. The 

Uafaitanta of SanU P^ hunt these insectsi to eat 

tfacB. They make omelettes of them, or, after 

kcvlng frieil them, they cover them with sugar, to 

make comfits of them.— CAemisf. 



PREPARATION OP PURE TELLURIAN, 

DT UEHZELirS. 

TftLtv&ST of silver has lately been found in 
Siberia, and telluret of bismuth at Schemnits. 
Berzelins hat obtained the metal in a pure state 
from the former by the foUowlflg process : — Ma 
dry carbonate of potash intimately vrith the wdl- 
pulverized mineral, make it into a thick panto with 
olivf oil, and put it into a porceUiu crucible with a 
cover. The crucible U then to he at first gently 
heated, till the oil is carbonized ; and when gas 
ceaacs to bum at the edges of the cmcible, the heat 
is to be raised for a moment to whiteness, and the 
prucible then allowed to cool. A deep, brown, po- 
rous mass is obtained ; it is to be quickly 
powdered in a dry mortar, and tbrown upon a dry 
lUter and washed with boiling distilled water, with 
as little contact of air ss possible. 

A liquor of a rich red color is obtained, which 
vrhenevcr it comes in contact with the air, beoomea 
of the lustre of silver ffom the tellurium which 
separates, while the potassium oriditea by the oxy- 
gen of the air. As soon as the Uquor passes color- 
leas, the mass on the filter is sufficiently washed. 
and is composed of charcoal and bismuth, uonUuning 
mere traces of tellurium. 

Thf deep red solution contains telluret of po- 
tassium mixed with more or less sutphuret and 
Beleniuret of pota«Gium, with a small quantity of 
telluret of gold, copper, manganese, sua iron. If 
the solution be suffered to remain at rest, the surface 
becomes covered with a pelhcle of tellurium, and 
gradually, but very slowly, it becomes turbid to the 
bottom : by blowing air ioto it the mus oxidizes 
readily. The potnssiom becomes potash, and the 
tellurium is precipitated by oxygen- When the 
precipitation has ceased, the solation assumM a 
green color, and if it be poured oil' at this moment, 
it deposits in a few seoonds a very small quantity of 
tellurium, and the liquor becomes yellow when the 
precipitation has ceased. The green color is owing 
to a mixture of the blue tint occusiooed by the 
small quantity of tellarinm mixing with the yellow 
color of the liquor. Sometimes the remaining 
liquor is of a dull ro^e color, and gives no precipi- 
tate in several days ; this is owing to the telluret of 
.iron which it contains. 

As long as the potash is in access, the sulphur 
and the selenium are not precipitated, but the aecelB 
of air converts them into acids ; this is a method of 
obtaining tellurium free from these substances. 
Muriatic acid precipitates from the yelluw solution 
the selenium and the sulphuret of tellurium which 
it contains, in the state of sulpfauret and selcniuret 
of tellurium. 

The tellurium precipitated from the alkaline solu- 
tion is a very fine and dense powder : it must be 
purified by distillotion ; bat on account of its ^ht 
volatility it cannot be sublimed from a retort in a 
common furnace. In order to effect it, a long 
porcelain ve&sel, containing tellurium, was put into 
a large porcelain tube in a furnace ; it was healt:d 
to redness, and a current of hydrogen gas passed 
over it. The tellurium was converted into vapour, 
and it was constantly carried by the hydrogen to- 
wards the eold parts of the tube, where it was con- 
denaed. In order to make the tellurium flow after 
its condensation, the tube must be slightly Inclined. 
In ■ short time all the tellurium distils, and there 
remaiw in the porcelain vessel a small button formed 



128 



MAGAZINE OF SCIKNCE. 



of the telluiTts of ^1d, copfHtr, oud iron ; Uie pro* 
duct of the dutiUation u pure teiluhum. 

In i:<^neral the proceu. which consists in fusion 
with pota>!iHTiiirhiirco«l, may be employed to purify 
teUurium, rsjieciiilly if it contains mlphur, selenium, 
or anenii:. all bodies vMch cannot be separated 
^m it by distillation. The oth uic goes ofl* in 
vapour at a red heat, and the two others, after the 
piecipitation of the tellurium by the air, remain 
oMolved in the liquor. The solatiun of potash 
eontteilUl the metals which render the tellarium im. 
pan. If in this operation powdered charcoal be 
employed instead of oil, the mixture may be strongly 
heated at onee, but the solution of telluret of cal- 
cium ; and u the lime which Is produced is preci- 
pitated with the metal, the precipitate must be first 
washed with mariatio acid, and then with water. 
The quantity of charcoal ought always to be soJh- 
dent to preTenC the mass A'om fusing during re- 
duction, for then it would go over the edges of the 
crucible and part of it would ba loit. 



OS THE COLORS OF FLAME. 
Tb the Editor. 

Stm.— Allow me to ofhrr a few remarlts conccraiog 
the color of the flame of a candle, in refutation of 
an article of one of your correspoudeats, which 
appeared in No. 63. His theory U certainly 
■itogether new, and I may say somewhat obscure, 
In consequence of making carbon the OH/y motter 
cooled during combustion ; tallow, wax, oil, and 
moat of the oleaginous combustible bodies, being 
Gonpoaed of carbon and hydrogen, with a small 
portion of oxygen \ when the caudle is lightnl. the 
two former are given off in the form of carburettcd 
hydrogen gas, and is precisely the same in its com- 
portion as coal and oil gax ; so tliat the Haine of 
the candle is caused by the ignition of this gas, and 
not of csrbon alonr. If " the carbon at the lower 
part of the flame were ^tctuatly burned,*' the tem- 
perature at that part should be greater than in the 
higher portion, where it is "not completely burned,'* 
whereas the contrary is the case; and as regards 
the " unburned rapour of carbon" in the interior 
of the flame, it is well known to chemists that it is 
capable of existing in the form of vapour, even with 
the greatest heat we can produce, unless combined 
with some other gas ; so that the very proposition, 
being false, the argument falls to the ground. 
Taking then as an esUhlished fact, that the flame of 
a candle is nothing more than rarburetted hydrogen 
gas in a stale of combustioD, we can easily account 
for the rarioDS colored parts of the flame. When 
a candle i« first lit, the wick alone is consumed 
until the flame approaches sufficiently near to melt 
the candle ; the grease' is then drawn into the body 
of the flame by the capillary attraction of the wick, 
and is there decomposed by ignition, and is given 
otC in the form of carbunitted hydrogen, and this 
coming in contact with the atmosphere during 
combustion, is again decompoaed by the oxjfren 
uniting with its carbon and hydrogen, forming 
o&rbooic acid and water. The higher the tempers- 
ture of flame, the greater is its brilliimcy, con- 
aequentty. the lower port being constantly supplied, 
with a current of oool air, its temi>eratnre is 
diminished and the flame beuomos blue at that 
part, while the air which abstracted the beat ascends, 
and preserres s warm atmosphere around the upper 
portiOD. To prove this, Profenor Donofbn. of the 



Royal Irish Academy, construrieil a cylinder of fcea 
opt n at both rndx. and iaclosed in it a jet of (f«S 
gas, when the dame ajutost constantly bccarr^- '^*''- 
and after Sfinie timr went oat. Again, if 1^ 
wire in the white pare it becomes red hot, it : . 
pass it into the blue portion it is tnstanUy nooloL 
In a jec of coal gas ws observe a larger portion sf 
the blue color, then In the flame of a candle, oa 
account of the metal being so much better a ooa* 
doctor than the wick ; but if the metal be heated 
to whiteneM, or a taper held immediately below At 
flame, the blue color disappeara. This blue color, 
howerrr, ia not conflurd alone to the lower part ; 
fbr, if we hold some object betweeo the eye and the 
flame, so as to exclude the dasxliug light, we shall 
ohaerre a fiiint rim of blue encircling the upper 
portion as well, which constitiitei the extreme rdg« 
of the flame, being in immediate contact with the 
air. Flame is nothing but a hollow cone, whose 
surface is the ignited film, which is supplied with 
gas from its reservoir in the dark central portion \ 
for if a sinsll tube be insrrteil therein, it Dtay be 
either drmwn off and collected, or it may be Igooted 
at the extremity. That there exists a very low 
temperature in the centre of the flame, is evidtnl 
from the deposition of carbon which takes place oa 
the wick, which being a noU'Conductor of beat, 
maintains a lower tem|>erature than the Tspour 
which surrounds it \ when the vrick reaches the 
ignited portion of the flame, it abstracts a portlun 
of the heat in order to be consumed ; it is, ooa- 
sequenlly, incapable of consuming so much gresaa 
aa before ; the snperabundaooe therefore overflows^ 
and runs down the side of the candle, the com- 
bu^on is imperfect, ■ portion of the carbon k 
carried off unconsumed in the form of smoke, the 
candle gives less light, and requires snnlfing in 
order to get rid of the obstruction. The veQ 
known experiment nf blowing out a candle ax>d 
nilighting it from the smoke, result! from the 
stream of carhuretted hydrogen gas which issues 
from the wick. When a cold mntatlle plaoe is throat 
in the centre of a flame, the carbon of the gas ia 
condensed before it comra in contact with the 
atmosphere ; but if the candle be held directly 
above the flame, tio carbon is nmdensed, as car* 
bonic acid, and water alone comes in contact with 
the plate. The cause then of the varioos colored 
parts of flame may be staled u follows : — The 
lower part and edge of the flame are bloc, in con- 
sequence of being sahjt-ctrd to a lower, temperature 
than the rest ; the interior bein^ hollow where nn 
flame exists appears darker ; while the other portion, 
Uiog in a complete state of ignition, ippean Ibe 
brightest. i. 



MISCEIJ*ANIES. 

Ga$JTom Graptf. — An interesting experiment haa 
been made at Bonrdeaox. on the husks of grape*, 
when presiied, and the lees of the wine, in order to 
show their use for the ptirposes of lighting. A 
ponnd of the dried husks pat into a red-hot retort, 
gnre, in uneu minntrs, !£00 litres of gas, which 
burnt with an intense light, and free from unoke or 
xmell. A second experiment with the dried Icciwaa 
equally satisractory. 

The Mulberry. — M. Seringe argues from physio- 
logical facts, that pruning the mnl))erry at the same 
time that the leaves are gathered, wilt produce n 
handsomer and a longer-lived tree, and a grc«tv 
abundance of leaves. 



Lanaaa:— P«iit»d by O. FMacts, 6. Wlutsllmo Unt. Uito Fad.— rubUshsd by W. Usihaik, II, PatorwMtar Bow 



TUB 



MAGAZINE OF SCIENCE, 



anil Stfiool of arts. 



KSW EDITION. 



{lid. 



^y^^^tf^^^^^i^^|^i%/^^^^| 




APPARATUS FOR LITHOGRAPHIC PRINTING. 




u. — no. XVII, 



130 



MAGA21NE OP SCIENCK. 



LrmoGRjiPHT. 

(RmmmM/rom pmfe WO.) 

Wk km \m libc femus f«pen «paa lU» 
g(M« M «cno«a( of iWiloan 
tfdM wed is <Im wt ; •« a« , 

itsrtir to lirirrihff dw a^ 
<nir of Cbe ssipter 
tin ft fslart orportsniKj Uk 
J la tlM 4ra»tM aod iwintbif . m vcU m on 
oOwr a«ttca «oaM«ted vilh the mfe^cet. 

Ftf . Ill thfl i>Mr iVwf — An Hitinunant^ chap, 
•Mf to mmMhmon, nprdttiott* in worliinc. sad 
iiAwUfl pArtintUrtx to eanli. imsll Hmdan, ftc.— 
for tarr*Y wot k the prM Ofo to not tvfScsefit. 

*> ^-ommoo itronf ubie. boTtng 

ft I 711, ban to inpporC the tiprigfat 

pf> «uppor1« tifr ttoDB I. C is a 

^I' '-'fTcrtd widi IgathtT, cxftctly like a 

pT-.T j.jia U with p&rchment ; thu is large 

•doukU tu itivttr Ibe ftonc and ii capable of Iwing 
< fcr oi'rB tMctc or hrmight dows upon the tCooe, by the 
htnget or ptTotc nhicli coiuuct it with the table — ^it 
U Q4ual)]r supported on it4 pirota at nch a height 
» 10 f«ll flat down npon rather a thia itoae. The 
oprigbt D Khoald be a» long aa poasible, aa the loDger 
it la, the more equably the icrBper work* on the 
atone. The croi* bar E ii of course capable of an 
ap ind dowti motion, oni itii height, and conae- 
qiirntiy the height of the scraper U, which is attached 
to It, i« rccnlaud by an iron pin put through one 
■or other of the hole* H, at the upper part of G G. 

II, tbr Rcrapcr, la made to hare a awingjng motion 
baokwird« anil furvrnrdi tn the socket at the top, 
where It i« conTuirti'd with E. TUr tcrapcr itself ia 
forrawl of boi wood or hard mahogany, and tits into 
• joint cut to receive it— it ia futeuixl by n pin or 
■crew, only fufflciently tight to keep it Ati^ady, being 
allowed neverihelcai a liUl<> piny liiJcwnyii. in order 
lo aoeouimodate Itself to the Atone ; if this latter 
ahould be bigber on one itdc than thu ulbcr — thus 
by means of tbrfir various odjiutmcntti, the scraper 
can Im) muved lui^ily In orery direction. The lower 
rnti of (3 it fupd by a ninviMhlr joint into the (rendlo 
l>rnrulh. By lll^a^iag ou the it-cadlc, tlip scruper is 
funibly prrnaitl upon the atone uiid worked with tlie 
hand, by pulling it bncktvanlii and forwnrd*). It 
atuml'l 1*0 niiMilittiird ibiil tli'' p'.'lc which supports 
lh» wrapFr. ihoubl be mndr of two parts joinLed to 
eaub othvr, so (h«t nhc>n the printer draws the 
teruprr lo liiin, llif nhnlc ahnll fnrni one straight line, 
and when hi- puihcv it awny, it btnils back. In all 
preoia the leathrr must be stretched tight and welt 
f(n>iueU at the back, to enable the acrapcr to alido 

f i(t. 2. — Thf Tall* for ruVtitng doit^ the 
ffioifK.—Tliln t.iblr In upcji nt the top, nnd hoa two 
cro^K-bara to I'ly the Htonits oit. The boitom of the 
t^ble eltipQ* loAnrdit the Itole, Inordrr to IK the sand 
and n-Nler run out tu a tub pUr<*d uiulcmeath for 
that porpote ; the sand vbion fallii in this tub may 
Im (Irird, and when sifted, ierrea for l^nc graining the 
alonrM. 

Pig. %.-^BUhiHff fhs. — This box mar be made 
of any aJH ; ft mnnt be watcr<tight. and have two 
pteora of wood with notrhoa fixed in its bottom, 
ih*- •■ "^ ■■ li^n it 1m bring etched, must rest on the 

IMil ■ 'T* iif WiHid. 

* . 'ti-rfnr Charyimp ike ItrawiHyt with 

Primttng ShA. — Thrao rollers may bo made of any 
tCBiitb, but must not bo leas than tour iuebca in 



nej- are 



ef aUer 




at IW c ali t mily of Ite 

t^ whole is covered with a calTa-aUa^ M 

gRst care, and w as to fil tagfaOy. Tfab 

8B perfOTved aa follows : — the caira<^tD 
atrctdkedoB a board with nub, aod aOowi 
it ia then cot ao aa to At tbe roQer ««a 
nraat be aewed with silk, and with what 1 
can a dosag-sutch ; this must not be per4 
the roOer, ^t sfparateW. and with the so 
OBtwards ; when the aeam is finished the 
be turned with the rough aide outwardly a 
sDpped on the roller Uke a glore -. the e 
(the skin being cut longer than the roUer 
tied together with a string or oaikd 

Aa m taming the rollers on the etooe th 
might hurt Che printer's hands, two little ' 
estployed, and ao made that cm their 
more or leas on the wooden handles, they « 
or lesa easily ; this effect may also be (real 
by the preasure of the bonds. 

This mode of holding the roUen ti 1 1 
portaot thing in lithography, and a liti 
printer ought to study it with the greated 
be perfectly understimds how to manage ( 
he may either force the stone to receire fl 
or take it up from the stone ; in abort, be 
aa be likes the effect of the printa, and era 
the entire tint of the impressions. 

As the Atones for ink drawings are poUil 
not so easy to moke the rollers tuni 
which case wooden handles are substitute 
leather ones. 

In pnsamg the roller, which U 

E renting ink. over the stone, tho«e parts «1 
een preriooaly wetted will of coarse 
reccire it, while, on the contrary, the gn 
will attract it, according to the intensity vd 
they are drawn, and tlie difTerenoe which 
tween the several tints will depend emivd 
vnrird effects of the drawing, and on the 
which the printer will press with his roller^ 

In order to prepare a roller for reed 
printing ink. it mast be held near the fira 
besmeared with lard, which must after 
scraped off ; it must then be worked fa 
three days on the table with printing in] 
then fit for use. 

If a roller i» to be laid by for more 
night, the ink must bo with care scraped « 
most be besmeared with hog's lard. 

Pig. 5 is a Sttel Pen with a screw for 
straight lines : this is an indispensable im 
for drcLwiog lines : the sides must be 
bent than those usually found atinstrumenfi 
this is done in order to enable tbo ink to $4 
tn the point, which otherwise it would not 
the points of this instmmeat soon get Uoal 
the moment that is the case, they muat b^ 
with great care on a hone with olL Tliis \ 
delicate operation, as the fineness of the 
pends entirely on the points being peried 
and eren. 

QLuU-i and pens are -very soon blunted 
nature of the stone and of the ink ; steel 
the only ones that con be used. These 
otU if a very thin piece of steel, which must 
in the fvrm of h'sif a cylinder ; cut 



MAGAZINE OF SCIENCE. 



131 



tempered, ond then ground on ■ 
i arc fixed oa b commaa quill, 
r pencil U mUo an mdupensable 
of the hair must he cut oiTwilb a 
that ouIt twelve or foarteem hairs 
pencil thtw prepared, and the steel 
instruments with which drawings 
ented thac can eqoal engrariusa in the 
the lines. 

scraper* for scratching out writing 
renient for lithography ; it is better to 
of square steel, shapetl as represented 
and 7, ground on a sconCf and fixed in 

(Ta be' continued.) 



PHE NEW METAL LATINIUM. 

I C. BOOTH AXD CAUPBRLL HORFIT. 

is dertred from the Gn^ek Xayravuv to lie 
called in Swedish and German Lantan, 
iliah Lfttanium, for the sake of euphony 
with the generally reciTcd tenni- 
es of the elements. The ordinary 
cerium by precipitation with 
potjusa, threw down a bisolt of 
B time, the latter constituting 
bole saline mass. The method 
the two drpt'ods on the ready solubility 
latanium in dilute acid after if^aiLion, a 
by cerium under the same circnm- 
m its nitric solution, it may be best 
as 8 white, crystalline carbonate, by 
ammonia, and from this its other 
be farmed. The dry chloride heated 
reduced to grey melallic powilcr 
lead color, and capable of being 
by pressing. It is slowly con- 
in tlie air, and in cold water into 
with the evolution of hydrogen. 
t«ke* place in hot water. 
Isomeric states. The ordinary salts 
t reddish tinge, bat when the yellowish 
heated in hydrogen gaj, it becomes 
m fhint shade of green, and dissolres with 
in odds, forming aolta which possess 
bae. 

ate of poUisa it forms a slowly 

h howc\cr, does not precipitate 

ding Ball of cerium , unless the 

t in the solution. Its atomic 

er ihon that adopted for the oxide of 

Botiea is mainly extracted from Ber- 
to Foggendorff, publtahcd in Nos. 4 
id. Annals for the presoit year, 
its were aa follows : 

tared the sulphate of cerium and 
(Ordinary methoUn from the mineral 
lived in a large ([nantity of boiling 
Chehydratcd oxidei) of cerium and latu- 
Htated by caustic potassa. These were 
fn nitric acid afLer being llioronghly 
raporatcJ to drynets, and healed in a 
>le until all the nitric acid was ei- 
Olides remained uf a li^bt reddi«h 
r, mid were transferred to n glonn cnn- 
tric acid diluted with 60 (0 80 times as 

iMratttitbsrIoia lti« compouod orcerlmii. 



much water. After digecting about two hours In a 
gentle warmth, the latanium is dissolved and oxide 
of cerium remained of a reddish>browu color. 
The solution treated with caustic potassa threw down 
the white hydrated oxide latanium, much mora 
bulky and gelatinous in appearance than alumna. 
It is exceedingly difficult, if sot impossible, to wash 
it out tbroDghly, for after edtxtcorntion for sevetsi 
days, the liquid passing through the filter still gara 
indications of a solid matter, and «Lmost tod to the 
belief that] the oxide was slightly sohihlr in water. 

On re-dissolving hydrntcd oxide in nitric acid, 
evaporating to dryneu, and heatint; to redncu the 
dry oxide remained of a brick-red color, difTcring 
therefore from the oxide of cerium by a lighter hue, 
and by containing less of brownish shade. On 
treating this oxide oa before with very dilute nitrfc 
acid, a small portion of oxide of cerium remainedr 
proving that this mode of separating the two metals 
is not accurate, and that we must await further 
expcrimenta for the discovery of a mort perfect 
method. 

* Curbonate of latanium, as thrown down by car- 
bonate of soda, is a voluminoua white precipitmte« 
and, like the hydrated oxide, very fUfficalt of edol- 
coration. for after obtaining the chloride from it, 
crystals of common salt were also risible. Agree- 
able to the observations of Mooander, therefore, the 
carbonate of ammonia ia the beat precipitant. 

Sulphate of latanium, aa readily formed by the 
Bohition of the oxide, or carbonate, in dilute aul- 
pburic acid, evaporation to a small bulk by heat and 
exposorc to Bclf-cvaporatton, while delicate needle* 
of a fleab-red color collect in little groo[>« on (he 
bottom of the capsule. 

The chloride is similarly formed by means of 
chloro-bydric acid and evaporation. It forms a light 
yellowish green crystalline mass, In which no deter- 
minate form was observed. 

The quantity of latanium in oar poaiession was 
so small, amounting only to a few grains, that the 
ojjeratiDoa were necessarily conducted slowly ond 
prevented onr pursuing them qoantitativcl|r. Should 
we be enabled to obtaiu a larger amount, we may- 
give more interestiDg results, without, howerer, 
trespassing on the ticld legilimatly belonging to the 
discoverer. — Framiiin Inslitute, 



INDIAN MODE OF PREPARING THE PER- 
FUMED OILS OF JASMINE AND BELA- 
Dr. Jackmjn of Ghoaeepore, in a letter to the 
editor of the Asiatic Journal of Calcutta for June 
1B;19, Bays;— In my last communication on the 
subject of roee-water. I informed you tJiat the 
natives here were in the habit of extmcting the scent 
from some of the highly-smelling flowers, such aa 
the jasmine, &c., and that I would procure you a 
sample, and give you some account of llie manner 
in which it is obtained. By the pre«nt steamer, 
! hjiVB rtwpotched two small phials. conUiuing some 
of the oil procured from Jsflnine and the Bela 
flower. Eor this purpose the natives never make 
use of distillation, but extract the essence by causing 
it to be absorbed by lome of the purest oleaginoua 
seeds, and then expressing these in a coriimon mill, 
when the oil givtat out has all the iceut of the 
flower which has been made use of. The plan 
adopted is to place ou the ground a layer of the 
flower, about four inches thicJt and two feet iquar 
over this they put some of the Tel or Scsaiaum seed 



132 



MAGAZINE OF SCIENCE. 



wetted, 4hoQt two iDchM thick md two feet iquare ; 
on tbU ftgaiu ii ^ilaced another layer of flowcrii 
about foar iache« thick, u in the first inetum ; the 
whole U then covered with a sheet, which is hrld 
down by weights aX the end« iind atde«. In thU 
itatfl it ii lUowed to remain frutn twelve to eighteeo 
hoars; «ftrrthis the flowemare removed, and other 
layers placed in the lame way ; this aUo is a third 
time repeated, if it is desired to have the scent rery 
strong. After the hut proccsi, the seeds are taken 
in their swollen state and placed hi a mill ; the oil 
is then expressed, and possesses most fully the scent 
of the flower. The oil is kept in prepared »kiiif, 
called dabbers, snd is sold at so much per seer. 
The Jasmine and Beta (Jasminum sambo) are the 
two flowers from which the natires in this district 
chiefly produce their scented oil ; the Chumbol 
(Jasminum grandiflonun) is another, but I hare 
been unable to procare any of this. The season for 
manufactnre tfl coming on. The present oils were 
inanufactared a year ago, and do not possess the 
powerful ftcent of that which has been recently pre- 
pared. I>ifttillation is never made use of for this 
purpose, as it is with the ro&eA, for the eitreme 
heat (from its being in the middle of the rains when 
the trees come into flower) would most likely carry 
ofl* alt the scent. The Jasmine, or Chymbfle, ss it 
is called, is used very largely amongst the women, 
the hnir of the head and the body being doily 
smeared with some of it. The specimen I send you 
costs at the rate of two rupees per seer. 



ILLUSTRATIONS OF BOTANY. 

OUnmed from page 109.^ 

Class VII. — UzpTAWDxiA. Four orders. 



^ 



-f laots m\fh r tUmf ns. ami 1 , 2. 3. 4, or T stjlss. 



\M.m^ 



The noble j^scnlos or Horse-chesnnt belongs to 
this small class, wliich contains but one British 
plant, the Trientalis or Winter Green. Tlie beautiful 
Calla Ethiopica liere finds a situation, as well as its 
congeners, the lurid and mottled Dragons. Beyond 
these there are no plants of either beauty or interest, 
except indeed the neat little white-flowered Septas 
flpom the Cape of Good Hope, which has its calyx 
of seven sepals^ its corolla of seven petals, seven 
stamens, seven pislits, and seven capsules. 

CUsS Vni.— OCTAKDBIA. PoUF OrdoFS. 




riaab wiUi a itAmsu, and 1. S, 3, or \ 9tyl«),^ 

K class of lovely plants, oontainuig the e1«^nt 
Heaths, of which there arc perhaps three hundred 
■pMies, most of them nalivcs of the Cape of Good 



Hope. The annual, commoaty called KsKtnrtiasa* 
bat properly TropKolnra or Indian Cress, is b«r« 
too : and so are also the splendid Fuschio, ihe tweet- 
smelliog Evening Primrose, the ^'hortleberrits soif 
the Craabcrries, the Me2ereon« and the Laoe-bBk 
tree* so called from its being fonoed in layers, thit 
when separated exactly resemble lace, and is ujMd m 
SQcb by the natives of tropical islands, are oU cf 
ordrr Monogynia. The plants of iototest in ths 
other orders arc Persicaria and the Soap Berry is 
the third, and tlie four- leaved Paris in the last order. 

Class IX. — Ennbamdria. Three orders. 




riaots with 9 tianns, sad 1 . 3, or 8 ttylea. 



I.-I-.H 



As in class Heptondria, there is here but one 
plant of native growth, though one of considerabl* 
beanty. the Bntonius or Flowering Rash, common 
enough on the banks of the Thames around Lon> 
don. Of foreign plants, the Cashew Nut aiKl tliB 
family of Uie I^aurels, as it contains the SassafraSt 
the Cinnamon, and the Camphor Tree, as well u 
those which produce the Gum Benioin and the Alli- 
gator Pear, must be considered valuable, so also tha 
Rhubarb which i<i placed iu this I'loss. The BuCo- 
m\is belongs to order Uexag^'uta. 

CUsi X.— Dbcandbia. Fire orders. 



rionU witfa 10 itsniens. sad 1. 1. 1. 9. sr 10 atylM. 

So common is it for phints to have their various 
parts arrnnget) in fives or tcnA, that these classes are 
extremely extensive ; the present, for example, ooo- 
tains perhaps 1000 species of plants, which aro 
somewhat varied la charoctcr, most of them pretty, 
few of them splendid and majestic in port. Hero 
ore very Dameroos pspilionaccoas planL^. a circnm- 
stmic« necessary to be remarked on account uf tlto 
class Diodelphia, which consists wholly of t'"^*' 
Independent of the leguminous or papilii : 
plants of Decandria, there are snmn of grn< . 
tercst and favorite culture — the Pink, and its farie- 
ties the Carnation and FicoLer, will always br ad* 
mired; so will the Rhododendrons, the Kalmiss, 
the Arjdea, and the Arbutus ; the Cntchtly, the 
Chickweed, the Lychnis, the Corn Cockle, the 
Stonecrop in its many species, the Oxali>, and the 
pretty moss-like Saxifrages ; nor is it cosy to deft> 
X pise the noble Mahogany, the Logwood, the Bntsil 
Wood, and the Lignum Vitee tree. 

To the first order we munt refer tl»t greatest of 
all vegetable curiosities, the Dionea Muscipula, Or 
Venus Fly-trap, which catches the injects thst set- 
tle upon it. In tlir gwamps of Cnrulina it isahan> 
dint, llere, though not capable of living in tte 



MAGA2INE OF SCIENCE. 



133 



{■ of euT culcttrc in the hot -Louse, 
•ee<lfl Arc aontlalty itnj»oite<l. 



for 



XI. — DoDiecANDRfA. Slx orclers. 




from 13 lo 3U fllampns. if^tod on Ui« rtcepticlc- 
juul l.ie^S, 4. 6. u( I3tlyle« 



IM.i^.lMM 



^U rliLHK. but one rontaining tome goterid 
^L unoiitr wKieh is the lovely ood fragrant 
Bstte, (Kr^cda odomts.) la the same ge qui 
the Weill or Dypr'a Weed, a yellow dye of 
mble beauty, and wbtch decorates mofft of our 
|iits and old walls. The Aiarum Aurabacca 
K placed, fo alio that omimenC of our river 
fhc I^ylhrnm or purjilc Loowstrifc ; the 
OUT, and the well-known Hunse-Ieek, Uie 
I {>Uut wliicb is reiiiarkable in the regularity 
varioua partA, having twelve |ietal8, twelve 
19, and twelve styles. 

\am XII.— Ico8AifDRtA. Three orders. 




^k sameroui ■Umns*. fixed to Iho calyx, ntul wltHi 
K 1. >. 3. or maoy atyk*. 

Kofltloi 



^X^^ 



Itlon of the stameun in this, and the 
It before, aiid after, must be carefully ob- 
Here ibcy are always fixed to the calyx- — 
othcr» to the rec^itacle. This class contains 
)ua plant, the others have many which are 
belong iDOft of our fruit trees — the Apple, 
I, Cherry, Medlar, Tcacli, Apricot, Nec- 
lond, Pomrgnmatc. and Quince. Not 
but other plants of CfjurLl interest, the 
the Pimento, the Clove, the Strawberry, 
the Riiipherry and Blackberry, (both of 
spedca of the Bramble.) The " Queen 
,"the Roee, aJao hereholdf dominiou, aa 
beautifol funilies, the Cactus and the 
tfaemom — one species of which latter 
known as the Ice plant. 
lily of the Cactua bear flowers of the 
laplendour ; leaves they have none ; Btema 
)K distorted and extraordinary forms ; and 



roots so penetrating, that they iuniauntL* tbrnisclve* 
into tike intrrstires of the naked ri>t-k, where Ibe 
plants grow in luxuriance, though ajiparently without 
support. The Cactus FpccioBiftaimUR grow* well 
with ordinary attention, and is a frequent omnntenC 
of our drawing -rooms — thou|;b the emblem of short- 
lived beauty, never Lasting more thaii n duy. and 
often but six or eight hours. Tht* Cactus grarifli- 
floms, or Night -flowering Cereus, beara n tlower 
nearly a foot in diameter, of the most beautifully 
blended white and yellow, and of delicious fragmnce. 
It expands abont eight in the ereaing — is withered 
oud decayed in six hours afterwards. 

Claas Xlll.— POLTANOKIA. 




I 



Stimcni nomerous. and ELxvd to the recepimcW, ib«To(unr onikr 
tlk« (nilt. 



\.O.Si' 



The plant-i of this eharactrr are not always 
poisonou5, but are yet U> be viewed with suspicion. 
The Hoppy, from whose jnice we procure thednadly 
laudanum, belongs to Polyandria ; and also the wrlU 
knowu and numerous family of the Buttercups or 
RaDiinculus. The species cultivated with sudi earo» 
the Kanuncnlus asiaticus, is found of every color 
whotever, except blue. The Anemone U another 
favorite. The Water Lily who shjU pruifc too 
highly. Thr Colnmbine too, that emblem of fully 
— the fipleadid omameot of the Amerieun forest, 
the Magnolia — tlie pretty lictk l>arki^pur, the 
orangc-juiecd Celandine, the Traveller's Joy or 
Clematis, »o sweet and with sach feathery seeds — 
the Tea, and the Camellta, are all belonging to the 
class loossndria. Searching more narrowly, we find 
also the Caper bush, the Lime tree, the elegant, bnt 
short-lived, Cistus, the mngniticent Peony, the Tolip 
tree, and that celebrated and common tropical fruit, 
the Sour Sop or Cnstard Apple. The whole of the 
classes, perhaps, does nut contain o more ^iteudid 
coUoction of plants than ore here iooloded. 

(To Ut emtirmed.) 



ETCHING UPON GLASS, 

In the middle of the sixteenth century, when glasses 
manufactured in the Venetian states enjoyed the 
highest reputation throngbont Europe, it was com- 
mon to find those ornamented by engravings exe- 
cuted with the diamond. More than an hundred 
years had elapsed from that period, when Henry 
Schwanhanl, a pupil of Lehmiinn, waa incited by 
the acddental circum.<taDce of the corrosion of hia 
spectacle glass, to a method of etching on glass by 
means of some powerful acid liquor. His manner 
of preparing this Uquor was kept secret by him ; 
and as no fluid, save fluoric acid, with which we are 
acquainted, has the property of acting upon the sur- 
face of glua, while tlio discovaiy of this powerfWl 
menstmum was not brought before the world prior 
to the publication of Scbeele's experimenls in 1771| 
it is much to be regretted that the secret of Scbwan* 
hard was suffered to go with him to the grave. 

Tlie metliod pursued by tliis artist in the appli- 
cation of his discovery was differcut to that whicl; 



IS4 



MAGAZINE OF SCIENCE. 



u pnctued at pment. This is, to coat over the 
entire surface of the glui with vamish, and, through 
Ukia ooating, to truce out the intended flgures, leav- 
lag tlie glass exposed to the action of tlie add only 
in those parts which are to be occupied by the 
flgures. Schwanhanl, on the contrary, first traced 
the figares, and, hariog 6Ued the outline on the 
glass with variiifh, applied hb corrosive Biiid to the 
remaiader of the snrfaco. Bj this mean^ the figures 
were ItSt in relief, and with Lheir uriginal p^iliih, 
the effect of which was pleasing, and totally dis- 
similar to the oppearance of engravings with the 
diamond, which latter circumstance it ]irohjibIy wu 
that incited Che artist to the adoption of his peculiar 
method, since his productions would, by that means, 
be more readily distinguished from the works of 
others. 

The varnish employed by artists for defending, 
where it is requisite, the surface of the gloss from 
the corroding power of the acid, is osually either a 
Bolation of isinglass in water, or commua turpen- 
tine vamiiih mixed with a small proportion of white 
lead. 

By the aid of a rery few implements, the art of 
etching on glass may be rcndenMl a plroiung occupa- 
tion for amateurs. Good crown-gla^ is the most 
proper description tn be chosen for this purpose. 
Ilanng selected a square pone uf the proper size, 
this should be first heated by immersion in a sand- 
bath, and then rubbed over with purified bees* -wax, 
the temperature of the glass being such bm to cause 
the wax to melt compHetely and uniformly over its 
surfac«. The jmiie, thus corrred, must then be set 
n«ide to cool : and it ii important to observe, that 
every part of Its face must be protected by tliis 
coating of wax ; which, however, need not be thick, 
and indeed sboulil not be applied in sufficient quan- 
tity to render the gUas opaque. 

A paper havios the design boldly drawn upon it, 
may then be attached to the unwoxed under-side of 
the gU-is i and this drawing will greatly aasixt the 
Sftist In performing the next process, that of tracing 
the dengn through the wax. The best kind of tool 
for executing this operation Is a carpentej-'s brad- 
awl, which, as it ia flattened at the end in one 
direction, and rounded in another, may. according 
to the poution wherein it is held, lie easily made to 
trace lines having the requisite and different degrees 
of fineness. The point of a pcn-kuife, or any 
simiUr implement, may be used as a substitute for 
the brad-awl, and with almost equal efficacy. In 
tracing these lines, the artist must bo niindfiil thnt 
BtJ instrument Uys bore the BurfscD of the gUss 
throDghout the whole extent of the strokes. 

A>sha]iow eraporaUng iMuin of Wedgewood ware 
must next be employed. Its size should be such as 
will include within its area every part of the design ; 
and it roust at the same time be sufficit-ntly sninU to 
be completely covered when the pone of glass it 
made to rest upon its edge. Some coarsely pow- 
dered fluor spar muitt tlu'n be plocrd in the baain, 
together with a quantity of strong sulphuric acid, 
snfBcient to form with it a thin poxte, when the two 
aubsCanees must be well mixed togctlicr by stirring 
them. The quantity of fluur spar must of course 
be regulated by the stxe of the etching ; and it may 
be a sufficient guide on that head, to recommend 
that two ounces of the coone powder be used when 
the boflin is capable of contoinlng a pint : these 
basins are readily procurable from any respectable 
dealer in earthenware. 

As soon as the acid and fluor spar are properly 



iocorporated togetlier, the pana of glasa ahonld 
placed upon the basin, with the waxed side 
wards, and a moderate degree of beat mast be ap- 
plied to the bottom of the basin : somewhere betwwn 
120 and UO degrees of Fahrenheit's scale will fa* 
found most eligible. Perhaps the be«t mews s( 
providing a steady heat for this pnr]>osc is oflTenl 
by the sand-bath, which was used for heating tlie 
glass before applying the wax. On this «ub»^aeiit 
occasion, however, the tempentore must never tc 
sufficiently high to melt the wax, which in that cxia 
would run over the glass, and wholly destroy tks 
effect of the etching. 

Very soon after this ipplicadon of heat, fnmes oT 
fluoric ackl will ari*e copiously from the baJin, and 
attack the unprotected portions of the glass, WV^ 
the hamn and its contents are once thoroaghly 
warmed, the heat of the sand-bath may be advait- 
tageoiuly diminished. 

After the glass has been thus exposed during hal« 
an hour, it may be removed from the basin ; and 
first being rinsed in water, for the purpose of dilut- 
ing or washing away the fluoric acid, the wax may 
be scraped off with a cummmi table-knife ; the de- 
sign will tben be foand perfectly etched npon the 
surface of the glass. 

A metalUc basin will answer perfectly for gene- 
rating the fluoric acid; but it will be a|r'>>""*''^' 
improper to use any glaaed vessels for the j 
as the vitrcoDs coating of such would bt: ' < 
destroyed. 

In performing this process, it is necessary to ■#• 
some caution ; as finoric acid, if brongbt into con- 
tact with the skin, will quickly disorganise it, and 
produce wounds which may be painful and trouble 
some ; a very little carefulness will, however, aufiee- 
for preventing ony accident of this noture. 

When it is required thus to engrave other than 
plane surfaces, another arrangement must be pro- 
vided : the glass must be exposed to the fumes of 
fluoric acid in some deep ressel ; without, )iovie\er, 
being sufTered to come in contact with the pasty 
compound whence the acid fumes arise, aod ths 
whole should be covered over, to confine and rrtsbi 
those fumea, 80 that they may fully act opoa tlktt 
glass. 



PREPARATION OP PIGMENTS. 



i 



Chtfitnate qf Jjead. — This color is found q 
perfect in its natural stale ; that of commrrc« ia 
iRrtificial production. In its natural slate jl 
been known as " Siberian red lead.*' ! 
M. I'aiK/neltn analysed it, and found it 
combination of oiidc of lead and on H' 
ni«tnl, to which he gave the appelliitinn of " ch 
be««ase of the various colors which the ditfcrent 
preparations assumed. In fact, the chrontate of 
lead is yellow; that of mercury, red j of silrer, 
purple ; and the oxide of chrome is green, and \ery 
valuable for porcelain and enomcl. because it win 
resist a very high temperatare almoft without 
changing. 

Red lead, which was the object of M. Vanque- 
lin's enquiries, has hitherto been found only in Si* 
bcria, and even there it is not common ; so that tha 
laborious research of this learned chemist would not 
hsrc been of much ftdvantagc to painters. :f i' *- ' 
not been for the disco\'cry, in France, of .: 
rontaining a considerable ;M>rtiyn of oxide of 



MAGAZINE OF SCIENCE. 



135 



w- 



" vMe of iron. It hu also been found 
1 States of America, chiefly in Mnry- 
'^r,.ni Baltimore that ihc greater por- 
oe is eiported. The chromate 
■'. >vitb Uiis mineral by the union of 
Willi OLide of chromf , and at the Katne time 
ing potass with (hr Aciil ; thm derompoaiog; 
u^ rrtmmate of potass with solable nit of Irad. 

For Ibis purpose, one hxlf part of the nitrate of 

fOlasa is to be mlved vith one entire part of the 

arth conUiniDg oxide of chrome. This mixture 

li \hm M be calcined in a close crucible, nnd the 

— Iwtance Is afterwards to bo washed In warm 

wUrr, nlterrd, and thrown into a solution of acetate, 

or ttitrate nf lead ; and nothing more i^ required to 

KMiplcte the operation th.in to wash thn prccipi- 

tktt. In proportion as the chromate of potass 

b ia the neotml state, or that of Babchromate, 

ani! ixrcurdini; as the precipitation Is made In cold 

■1 water, the tint will vary, from a delicate 

.-[low to that of orange color. 

li is not, however, a permanent color, and is 

ie^ Ml in proportion to the oxide of lead it contains. 

' . ■ ' ^ years its bri;fht[ieas goesofT, nnd it becomes 

; >w ochre ; but when combined with alaminL', 

., ...^...liiiaes brilliant for a much longer period. 

Umiral yellttip fCAloride of /.Mflf;.— This is a 

nnm)iiruiiou of lead fuid chloriue. It is prepared in 

• ways: the following method by M. Chaptal 

f the oldest on record : — 

Four parts of litharge, reduced to an impalpable 

f*owdfr?. nre moistened with uoe part of marine 

I in four of water. 

Tmed into a thin paste, and to remain 
ii^urL>tti until it begiiu to whiten ; it must then 
ilBrrcd well with the spatala, to prevent it grow- 
too h<ud. 

In prnjKirtion as the consistency increases, lalt 

i« fi.iril ■ md if it appears that there is not suffi- 

ingredient, water must be added to 

tte in a proper condition. In about 

;:>ur hours this compound ibould have be- 

't-U bleached, rery compact, and quite free 

but it most still be stirred occa- 

■ •mplete the decom^msition: it is then 

y washed, to deprive it of the soda, 

found separated from the marlae salt, 

' paste most then be placed to drain 

6a a lilter. 

^%llen dry, it is reduced to powder, and exposed 
In the receiTcr of a reverbcratory furnace, until it 
a*4unirs Uk- tcUow color required ; Ibis powder 
'■ ' •■— to be thrown into a crucible which has l>ecn 
t np to a red heat, and is then returned 
>'■ furnace, where it is only allowed to remain 
^til ihe composition has melted ; ihus fufecd, it is 
dutwn on a plate of iron ; and when cool, it forma 
a erystalliue maaa striated transversely. 

The following is another method of producing 
ftiU pigment : — 

Acetate of Lead is first decomposed by marine 
•^' - the chtoriiir, as In the former instance, is 
' il from the soda, and forms a new combiiia- 
- <tb tlic leadf this chloride of lead is then 
urtfuUy washed, nnd when dry is mixefl with a 
quantity of pnlverized litharge ; it is then 
ted quickly in a crucible, and thrown upon a 
of iron ; but according as the mixtnro is 
for a longer or shorter time to llie action 
ftf ftrr, the yhnde of culor will be lighter or darker ; 
a* heat ii therefore to be kept eqUitl ; the crucibles 



are heated to red at Arstr and withdrawn at the 
same time. 

In the following proceu bismuth and antimony 
are used, nnd should bare the effect of rendering 
the color more permanent. They ore ground apart, 
that the proportions may be exactly ascertainedf 
which are as follows . — 

Bismuth 3 parts 

Sulphuret of antimony, .. 24 
Nitrate of potass, 64 

This mixturo is tu be dropped by degreea into a 
heated crucible ; when dissolved, it most be thrown 
into a vessel of water, where it is to remain, and 
must be well stirred for the requisite time. 

It must then be repeatedly decanted nntil the 
water has lost all its smell ; it is then to be filtered, 
and Uie oxide thos obtained is a fine powder, of an 
impure yellow tint. 

Au eighth part of this oxide perfectly dry, is then 
mixed with one part of muriate of ammonia, and 
sixteen parts of very pure litbai^. 

The fufflon is then to be carried on u in the 
English process : great care most be taken, how- 
ever, that the degree of heat, and the duration of 
the process, shall be exactly the SRme. It is as 
well to be aware, that the best crucibles will not be 
able to sustain more than three or four operations ; 
and also, that thry do not stand the heat, if kept 
exposed to the fire during a longer time than is 
re4)uired to fuse the mixture. Fifty years ngo the 
mineral yellow was not known ; it is not so per- 
manent as Naples yellow, nnd grows paler in time ; 
it may be used with the latter color and with the 
ochrcfl. 

NapteM YtUmo. — ^Tho discovery of this color 
belongs to high antiquity, even so far back as the 
earlier working of enamel. The Italians give it the 
name of Giallolino; Cennino Cennini writes it so : 
Paul t/omozzo styles it GiallioHna di Furnace di 
Fiandra f di Atlamagna : but it ia probable that 
when the French artists began to use this color, 
they obtained tt direct from Naples, where perhaps 
it was made of a better quality than elsewhere. 

There is in the Memoirs of the Academy of 
Sciences, a. d. 1772, an account of a process 
communicated by M. Fougeroux de Bondoroy: iC 
is as follows :— 

Ceruse 12 OB. 

Sulphuret of ontimoiiy •• 2 

Calcined alam •• b, ,. 4 

Sal ammoniac 1 

" These materials must all be rednced to powder, 
then mixed in exact proportions, and placed in on 
earthen pan covered with a lid uf the same material : 
this pan is then to be placed in a potter's farnace, 
wlicre it is to b« coletncd, first at a low heat, 
increasing it by degrees, until the vessel has os* 
sumed n moderately red appearance ; it will reqaire 
three hours of this calcination before this mixture 
is properly prepared. 

" The product of this operation will bo a fritty 
fiubstmce, of a golden yellow hue ; this frit is then 
thrown Into water, to separate it from whatever 
salts it may contain ; it is then groond, and ita 
tint becomes much paler." This process has been 
repeated exactly as directed, 'bat without success. 

M. Fougeroux has translated into the word alvm, 
the Italian expression, which in the receipt given to 
him, was doubtless, aUume de /ecia, that is, " salt 
of tartar ;" he is also mistaken in naming " su/frAu- 
rei of nntimony" amongst the ingredients, it is the 
** oxidf of antimony'' that should be nied. 



IdC 



MAGAZINE OF SCIENCE. 



lo a coUectiou of receipts reUtive to rarioua 
prooesws of the arts, priated at Venice, in 1753, 
b a memoir of Fosmci on tbe maaufactare of 
fmvnett mention in also made in it of the matertala 
for ooropoanding; Naples ycUow. AooordLng to 
tUat autbor it is Cliua prepansd ; — 

Antimony 1 tb. 

Lead \\ 

Common aalt 1 or. 

Tartrate of potnaa 1 

Ptuseri obi«nres, that bv changing the propor- 
tkna, the yeUow obtained will be of a more or leas 
golden hue. In four out of the six reoeipta which 
be g:ive9. there ia no meution whatever of marine 
talt ; the effect of thiii salt would be tu render the 
color more clear, but lea^ rich, becauae it produces 
a portion of chloride of lead (mineral yellow) which 
takea away the golden tint that originAlly chnracter- 
iaes the combination of the oxides of lead and 
antimony. 

In the monufactoring of Naplea yellow, it is of 
great consequence that tlic lead and antimony 
should be in the complete itate of oxides ; they 
mast be intimately blended together in tbe ^riadiag, 
and afterwards passed through a silken sieve ; the 
mliture ia then to be Uid in a vessel of nnglozed 
earthenware covered up, and piared in a potter's 
oven, in the least heated part of it, to prevent the 
danger of the fusion and de-oxidation of the lead. 

The yellow nsed in enamel paintiugt is very 
similar to Naples yellow ; it is composed of tbe 
oxides of antimoDy and lead ; by varj'ing the pro- 
portions* and alao the duratioa of ita exposare to 
the fire, different shades arc produced. 

M. Guimet'a yellow of antimony, which bears a' 
fine golden tint, more intense than that of Naples 
yellow. It is prepared as follows : — 

Antimonlate of potoai, or diaphoretic 

antimony, [carefully washed,) 1 part. 
Pure miniitm, 2 parts. 

These ingredients must be mixed carefully to. 
gether, and ground, upon a marble flng. to the con- 
sistence of paste ; this paste ia then to be dried, 
reduced to a powder, and exposed to a moderate 
red beat during four or five hours, taking care to 
regulate tbe fire in such a manner as to prevent 
ita rising to a temperature sufficient to carry off 
the oxygen of the lead and antimony. 

M. Guimet tliiiiks that tbe deutoxide of anti- 
mony, and the oxide of lead, are alone sufficient to 
produce as strong a yellow ; it appearing to him, 
that the potass has no other action in this case 
than that of completely oxidising the antimony, 
which process is indispensable to the success of the 
operation. 

1 iodide of Lend. — TIus color, which is not yet 
much known in commerce, ia as bright as orpiment 
or chromate of lead. It ia thought to be more 
permanent; but time only can prove its pretensions 
to so eseential a quality. It is prepared by pre- 
cipiuting a aolntion of acetate or nitrate of lead, 
with h3fdrochloiate of potass : the nitrate produces 
a more brilliant yellow color. 

(To be CQtUinued.J 

COPPER-PLATE PRINTING INKS. 

Tb tAe Editor. 
Snu — If the following receipts are useful they are 
much at your scrrice, they may be depended ujwn. 

Black. — Frankfort black, finely ground with 
boiled linseed oil, or (for very fine work) fat oil. 




Red, — Mineral ocaage red, 5 os. — C 
2 oz. 

Bive, — Celestial blue, 2 os. — marine di 

Orttru — Mineral green, 2 oi. — chrome 

BrovH. — Bojnt umber, 2 ok. — rose pi 

Liimc. — Pmsaian blue, I oz. — Chine»e 

Pi*fr. — Mineral pink, 2 os. — satin whi 

Oroji^e.— Orange red, 2 oz.— fiaVe whi 

[The above seven to be groond and 
Canada balsam.] 

Or, R*d. — Vermillion. 

Yvilow. — King's ycUow. 

Uiue. — SmalU. 

Grtm. — King's yellow — greea. 

Btite, — Prussian blue, and flake wlute. 

Brovrn. — Burnt nmbcr. 

Do. Darktr.—D'iXXo, and Frankfort bUdl 

Puce. — Frankfort black, and vermiUion. 

Brown. — Frankfort black, and drop lake. 

[Tbe above to be ground and mixed witi 
linseed oil.] 

(iold. — Gold bronze mixed with dark 
mahogany varnish. 

Silver, Copper^ Rv^, frc. — The sami 
gold, merely substituting the different brona 

JVo/e. — Cardx printed in gold, silver, &c,, 
when dry, be placed on a very smooth Ci 
still better, steel plate (not engrsTed) ani 
through a copper-plate press with rather 
pressure — this would also improve the app4 
of cards printed in Uke manner with letter-' 

Tb CfMis Q>pper'platef. — Copper-^ 
cleaned by laying them on the bob near the 
pouring on them same njiirita of tar, 
rubbing them witii a small soft brash, o. 

IPainfinff oh IV//urM.— The illuminated 
or coats of arms, &c., on vellam may ba 
by the above colors, rather than by Wi 
with gall in them as is often practised — < 
being put on with a brush as in ordinary 
also if more brilliancy be required 
silver, those meL<ils may be put on 
being first put on with gold size — gold 
with a bright transparent brown — silver wi^ 
tbey are also in a considerable degree 
colors as are nsed by Mr. Baxter, in his 
art of Oil Color Printing.— En.] 



.. 

i 



QUERIES. 

907 — Why are vegetable fibres, gucb ob Russia i 
■trotigrr wlwn wrl Uian f*h«a dry f 

SO^How is land paper for Ugbtlnft \ae\Trr* maM 

sou—Hour are ploaUr caatt bom Ufe Uken ? 

aiD— How it Mardvr't waterproof Jet uiude f— {1 
elmcd tf> tbloli Ibat this ii nothlcv more than lb 
blttf^kliig, for which there it a receipt tn No. 4a — B 

311— Huw !■ uold colored? 

S13 — Haft uJtiwcllfrB' ctMUent made? 

S13— How li blockiof cttmcQiuaed by tbe aim 



MISCELI^NIES. 

Nature of the light emitted by lirM, ^ 
state (f incaHdeseence. — Mr. Hcrscbel, 
amining the light from lime obtained by 
Drummond, found that it contains all 
rays, and three of those remarkable in qi 
quality, viz. the red, the yellow, and 
The red is intermediate between the red an4 
of the soUr spectrum, but is nearer to 
It is remarkable, as Mr. Hcrscbel menti 
red of the above character is yielded by 
whilst the colour given to burning bodies 
combiuatiotis of that aartb ia a brick red. 



LovMic^Prioted ^y D. Fhanoii. «, WUtaHent Lane. Mile Bad.~rubliilMd bj W. BainAW, II, pAlanwalw 



133 



MAGAZINE OF SCIENCE. 



BUSBY'8 HYORAULIC OailERY. 

or THK IKVKNTOR. 

lYi the Editor. 

Er^tatutitm tiftht Mnlioe Principle qf the Hg- 
Unuitic Ortxry, — Sia. — Some time iiace I wm en- 
((ii^efi. during my sUy »t New Y«rk, In a coHrEo of 
pxi»crimeiili to dctennioe the resittance oppotcd to 
sriltil botlit^ of various forms, in their psABBge 
tlin^ii^h fluids. To perform chesc In the most sim- 
pU urid dTtictual manner, 1 provided n large bason 
or circulor rewrvoir, and pl?ii*ed therein ntar the 
circmnfflreucc, any floating tc»«1 that happened to 
be the subject of trial. This vessel was connected 
by an arbor to a Qoatiug centre, held id its place by 
a small shaft passing through it, and erected per- 
pendioulsrly from the bottom of the reserroir. The 
bottom of tlie floating vessel was pierced, and a 
syphon which it carried, being soldered into the 
aperture, rose from it, and cxteotltog over the dr. 
cumference of the re«ervoir, ita other extpemitr 
de|>ended to air at a lower level than the surface of 
the water. Tliis outer leg of the s)7»hon wos closed 
BC the bottom ; but a minute lateral aperture, re* 
sembling a very small finger-hole of a flute, bang 
mule, the water spouted through it (when the 
lyphon was charged) in a direction parallel to the 
TCftscl, which instantly began to move with accele- 
rated velocity iu an opposite course. In a few 
seconds a maximum was attained, and the future 
progress exhibited that beautiful, coutinuuus roure- 
ment which can only find nn adcquatf coLtipnrtson 
in the silent glidinj; of the heavenly spheres. The 
idea instantaneously impressed me, and has been 
subsequently embodied, with the most encoaroging 
success, ill the novel machine above- men tiooed. 

At present I have applied the principle, nndor 
appropriate modifications, no farther thnu to the 
Sua, the Karth, and the Moon, whose oircoitj, ob. 
lif|uitie«, porallelisms. and rotatioDS, ore displayed 
in apparently spuutaneous movements on an area of 
five feet diameter. To effect these, three floating 
syphons are so eonibtoed in sun-i^hSiion, that ■ quan- 
tity of water equal to the dischai<rc of a single 
fltrenm about one-eighth of on inch diameter, with 
n lipad of about seven inches, elicits every action. 
Each motion, as in nature, is perfectly indepen- 
dent; anyone may be checked without impeding 
another; and when the hydraulic orrery commences 
its opcratiuns. it proctically Itliistnites those inci- 
pient and gradually accfl(?r.itin'; movements, which 
mijr be supposed to have tukt-n (diure within the 
miglity lysttm itself, when, as iu the beginning, the 
uiKximnma of the greater motions were probably 
attaitietl in .succession. 

This motive principle (founded on Barker's mill, 
but n'>w first combined with n Bypbou, and applied 
to a flrtAtiiig bodyl is Rppticnbli- to an extenaiTc 
variety of ex|MTimenta] and pbilosopbical purposes. 
It is 60 truly equable, that by meina of it I make 
the novel and interesting cicperiment of producing a 
perfect hydro parabolic mirror fifty. four iurhea dia- 
meter, and thus create any rongnifyiog power ad 
/I'AiYuM. Whirling tables upon Oils principle will 
presiTvc any pBrticolar velocity, during any required 
period of time, and the motion permits the most 
minute regulation, either by a variation in the length 
of the sy]>hon. or of the siie of the discharging 
ap^^rture; or by so fisiiig a small fleiible incUned 
e sypbun itself, and bending it into the 



arwnure ; o 
plane to th 



ttrram, ■» that any proportion of its re-Mtloa 

be neutralized b^ ttn lurtiun. 

Anoilier mean of obLaintngon univer>id stsnt 
of measure is hereby provided indep. 
pendulum. Tbui o given parabolic 
uvartably be formed by any given rut^iiun &t 
known level and latitude, and the focal distance i 
any parabola must nader those circumstao< 
always a given dimension. A jgradiuted mvc 
cirole will aUo practically meamre sui-b minntj' 
tiims of time as arc t)eyond the retc 
most accurate astronomical cbcks. i 
orrery, when in action, lowers tlic surface oi 
water upon which it floats about one inch ia^ 
hour ; it \* eflVctuolly stopped by blowinip air 
the syphons, or by preventing the efflux of 
any other manner. 

Cotuit rtiPtio fi qf the Ilt/drauUc Orrery, — Thel 
graving contains the plan and section uf tb« 
fdtus; tlie same lettersArr usrtl to point oat 
corresponding pnrta of the figures I and 2. 

There most f)r»t be imB|;inefl a circular re»c 
5 feet diameter, of which K i5 the centre, and 
pirts of the circumfrrrncc ; C C is a circulnr uni 
(11 inrhes mtemal, and 9 inchea external diameter) 
floating cooceutrically in the reservoir ; D >« a \ikr 
fixed diametrically acroes the bottom of th^ 
circle formed by the gutter C C, from the i- 
this bar a small shaft £ is erected ; F F i^ 
drical floating vessel 8) inches diameter, : 
soldered into an openinj; (one inch dioinetci ... .^r 
centre, tlie top of thtii tube is cln^ed, except a small 
bole through which the shaft E pa^^^ei!, ind a< t< ^i 
a pivot ; a cap covers the ccnlnil tube, atn' 
nates in a rod surmounted by a b&U (U in^. 
meter) reprcMoting the Sun ; G is o syphon •ulJjr'-.i! 
into an aperture In the floating cylinder F F, and 
balanced by a weight on the opposite side- ; the 
other leg of this syphon hangs over into tbc circular 
gutter C C, into which it dificbnr«/.<) a minute lateral 
stream of water, the re-action of which stream gives 
a rotatory motion to the vessel F F, and coo^- 
queully to the ball which it carries. Tlie v> ' 
charged into the gutter C C, passes away 
the tube H, beneath the surfoce of the great rc^rr- 
voir. and enters the floating rylindrlcjil chamber 
I I ; this chamber is 8 incheit dinmeter, is sur- 
rounded by a second cylinder K K 11 inches dia- 
meter, but the water of the great rcjemoir t« 
admitted through large apertures beucath into the 
intervening i^pace. 

Id the centre of the chamber 1 1, n tube one inch 
diameter is erected, rlnse^l altovr and below, fcicc|tt 
small central openings through which the 'I"'' I 
passes, ultimately heorini; a 3 inch biiUrepi' 
the Earth. In Uie circular »ipace between ti' 
ders I I and K K, floats a ring M M, h bar vhiifDiiii 
diametrically arrows the upper part of tiii« floating 
ling, and the fhal't l. acts as its pivot through « 
central opening. Upon this rinj; is erected 
•haft bearing a } inch ball reprweutitv' •"- ^'-^ 

On an opposite part of the riuL'. 
syphon is suldercrd into an aperture, m ' 
leg hangs over into the chamber I I, mtu tij 
part of which it discharges a smnU e>lream A ' 
the re-active force of this itresm rnunca Hi- 
revolve, and, consequently, to carry the br.;- 
scntiiig the Moon ronnd that by which the i^un 
detif^nated. 

The water now brought into the cliambcr 1 I. 
the two ayphuni which move the balla repi 
the Sun and Moon, is carried away by agrcdi i 



MAGAZINE OF SaEKCE. 



139 



^itJn; wtth it hjr a fthort hortyflntal 

■ fer Ib dischsTf^tl laffraHy at n lower 

^ t jTpiion mto un rv ' •• j 

:■ it, snrf it* re- 1 

--.' wholi! Bppiirfttii!>, .. it 

circuit in the gmxi reservoir repre- 

naual orbits of the Moon and Earth 

ii«m of the Enrth'i axic is effrrted, by 

u eirL'uliCr plate (G inches diameter) to the 

vitrrmit; of the rod L, and connrcrina: i*» 

mV/ti,';- by three eqoil oblique rod« 1, 'i, 3. 

nother circular plate fixed to the cen- 

■(rtm of the rcsp.rvoir; thus is formed 

ui o( (>rt.)jlar parallel rule, whirh produces the 

effect ; the latemt confinement of the central 

liiuntu being effected by mcang of the 

'-<i bnce 1, sliaprd \'\Vc a Kpiir, nnd 

fixed plate, itself being fixed to the 

y of (he tube U upon a biDge inca- 

.-.il ortion. 

lotigrr ann of the steel-yard Q (attached to 

ft L, and moTCJible on a vcrticsl joint) sur- 

the lo*er extremity of u slender rod connected 

mutersal joint K with the axis of the 3 inch 

■ Anudl ffhcol is fii^d upon thU rod towards 

md, and the cv^nical rim S, borne by and 

llrtt^ with the circular shaft which carries the 

m, acts upon the Kttle wheel by contact with 

nte;e. zivr^ it a rot^itory rantinn, coirununicjiCcd 

rhroagh the iuiivt'r«al joint to the globe 

(lie shorter arm of the stcfl-ynrd Ia 

jrn , u . . n. wiiL^ht just suflleient lu keep the 

ihrtX ^li-''l''v [Ti —t'li ai^inst the riiK. 

The uljluii^dj .if tht Sloon's path ia imitatt'd, by 
IMfiflir the inrUi^ry rod Hustainin^ the smnllcat 
1^ to tlide np and down Through t^n projrctioiut 
from the main xtaodurd as she revolves ; thta i^ 
by making o joint at V, und sttaehiiif; the 
.tremity to a revolving crank W, this crank 
to the continued axle of a thin vertical 
, Jl roUiDj; on the borixontal circle Y, which 
10, «nd borne by, the shaft snpportin^ 

T%r chaiij* of the Moon^i nodes is perfnnned by 
ciakins; a due variation between the diamelrT of the 
i^ti il ^1 <t-l, and that of the circle upon which it 
n*!)! r> • four balancers (6, 0, 7. 8,) are added, 
ftw the pui|>ose of keeping the apporaltu steady, by 
extension of the floating base. 



^Hfewtnii 



OhJECTS FOR THE KALEFDOSCOrE. 

( Returned Jrom paffe \\S. J 

AiTUQvaH the Kaleidoscope is capable of creating 
h^uHfol fonna from the most ugly und shapeless 
ohjrrit, yet the combinations which it presents, 
when ohtitincd from certain forms and colours, are oo 
toficnor lo tUu»e which it producvs from others, tli.tt 
idea LMU hv formiHl uf tlie power and elTectA of the 
tmment, nnlcas the objc«t« are judiciously •»• 



When the inclination of tiic reflectors is great, the 
objects, or the fraiiTnents of coloured gluts, kIiouIiI he 
Iwger than when the incHiiation is *maU ; for when 
mall fncmrnta are jiresentcd before a large apcr- 
tr ' •' *tfm whirh iff created has a spotted np- 

, I dcri^rs no beanly from the inversion 

vi --- ^ 5, in consequence of llit^ outline of earb 



Kep^rste fragment not joining with the innrtcd 
ircnye of it. 

The ohjecTB which giro the finest outlines by m- 
vcr>ion, are thofc which have a curvilincnl form, 
snch as cirt'lca. elHpHOit, lonprd cnrres like the figure 
8, curves like the fignre 3 and the luttt>r S ; rpirols ; 
and other forrn^, such as Ujuares, Trclani^le!<, niiJ 
triangles, may be applied with advantage. ' 
holh spTin :tn(l twistrd. and of all»cnlour» dihI 
of colours, shnuM be formed into the jircn- .i ■:_■ 
«hapc5 ; and whon these are mixecl with pitctts of 
flat-coionred glaif. bine vitriol, native sulphur, yel- 
low orpiment, differently coloured flnlda pncloi'-d 
and moving in xmrill vmsela of glass, Acc. they will 
make the finest transparent objects for the Kaleiilos- 
enpe. When the objects arc to be laid upon a niirroi' 
plate, fragments of opaquely colonred ghus should 
be B'ldcd to the transparent fia«mcnt*, a\ouff with 
pieces of brans wire, of coloured foils, nnd grains 
of spelter. In selecting transparent nhjecl»«, i1j« 
grentrst care mii<tt be biken to r^jf't^rt fragments of 
opaque glas<t, and dark colours that do not tranuuit 
much lii^ht ; and alt the pieces of spnn glass, or 
coloured plite9. thould be as thin aa possible. 

When the objcots are thus prepared, the next step 
ia to placr theiu in the object plates. The distance 
between the interior <iurfiices of the two pbue gta^ses, 
of whii-h till* ohji'ct phttea are composed, should nnt 
exceed l-8lh of an incli. The thickness of the 
trans{mrent glass nr«t the reflectors should be just 
sufficient (o keep the glass from breaking; and the 
iiiteriur di«inetcr of the brass rin^, into which the 
transfurent and the grey glass are burnished, should 
be so great that no part of the hnuj. rim may be 
apposite the angular part of the retlrctor^ ilnring the 
roOitory motion of ^e cell. If this prccnnlion is 
not attended to, the central port of the pattcTU, 
where the developement of new forms is grneratty 
the most beautiful, will be entirely obliterated by the 
interposition of the brsss rim. Whi-n Ihc two prtrfs 
of the object plate are screwed together, it should be 
nearly two-thirds filled with the nii:ttore of regubr 
and irregnlar ohjerts, already mentioned. If they 
fall with diflScuIty during the rotation of tlie ctill, two 
or three tnms of the screw backward will relieve 
them ; and if they fall too easily, and accumulate, 
by slipping behind one another, the space befwren 
the glasses may be diminished by placing another 
ghuw in contact with the grey glass. 

When the object plate, now described, is placed in 
the cell, und examined by the Kaleidoscope, the 
pictures which it fonns are in a state of ivrjKtunl 
change, and can never Iw fixed, and sliuwn to another 
person. To obviate this disadvantage, an object plate 
with fixed objects generally accompanies the instni- 
mcnt ; the pirres of spun nnd colournl glass arc fis&l 
hy a transparent cement to the inner fide of the glass 
of Ihe objott plate, next the eye, so thst the patterns 
are nil permanent, and may be cihlhited to others. 
After the ixW has performed a complete rotation, the 
aame pnttrrns ngnin recnr, and may therefore he at 
any time recalled at the pleasure of the observer. 
The same p»ttrrnB. it iis true, will have a different 
appearantx, if the li|;ht fulls in a different manner 
njion iho objects, but its general rharacter and out- 
line will rrniain the same. 

The object ptntes, which have now been deseribed, 
are made to fit the cell, but at the same time to slip 
easily into it, lo tluit they thnmselve^ have no motion 
^rparntr from that of tlie rrll. An object plntc, 
linwin-er, of a less diameter, callfd the vibrating 
object pUte. and t:outaiuing loose objecLi, it an in. 



i 



140 



MAGAZINE OF SCIENCE. 



tcrettini; addition to the instrument When the 
Kftlndoscope i« held horutontally, thi« mi»ll object 
|tla(« vilirutcft on iUi lower edge, either by i gmtlc 
motion uf the tube, or by striking it iliglitly with 
the finger ; and the effect of this vibntiou is sin- 
gulftrly fine, particularly vhen it it combine*! with 
the motion of the coloured fragmenti. 

Ao.'ther of the object iilates. in tereral of the 
instniiuent«t cootaini cither fragmenta of colour- 
lew glaM, or an irregular surface of tronsptrent 
vambli or indurated Canada balsam. Tliix object 
pUle gHe« Tcry fine colourleaa 6gure9 when u»ed 
alonio; but its principal um ii to be placed in the 
eel! between an dtject plate with bright colonre 
nod the end of the instrument. When thia is 
done, tltc outline of Uie pieces of coloured glaaa ire 
wfteni'd down by the refraction of the trtiuparent 
fragraeuts, and the pattern diaplsyi» the Bucit effects 
«f soft and brilliant eotouno^. Tlie colourless object 
plate flU)'plie3 the oalline of the pattern, and the 
mass of colour bcAuod fills it up with the softest 
tints. 

Rome of the object plates are filled with iron or 
brass wires, twisted into yahons forms, and rendered 
lifDSiler and flatter in tome places by hammeriog. 
These wire». wheji intermixtd with a few bidaII frag- 
ments of coloured glass, produce a very fine effect. 
Other object plates have been randc with pitch, bal- 
sam of tolu, gum lac. and thick tnuieparcnt paiota; 
and when these subsUiuces are laid on with jndg- 
ntent, they fo^m exaUent objects fur the Kalados- 
cope. Lace may be inlrodaccd with considerable 
effect, and also fcstoonti of beads strung upon wlr« 
or thread; but pieces of glass, with cut and polished 
iaees, are entirely unfit for objects. 

Hitherto we have supposed all colours to be in- 
discriniinatcly adopted in the selection of objects ; 
but it wrill be found Atun experience, that though 
the eye is pleased with the combiaation of rariona 
objects, yet it demea this phsasure from the beauty 
and BTtninetrr of the outline, ind not from the anioQ 
of many diflereiit tints. Those who are accnstomed 
to this kind of observation, and who are acquainted 
with the prmciples of the harmony of colours, will 
ioon pi^rceivp tlie harshness of the effect which ia 
produced by the predominance of one colour, by th« 
joxta -position of otlierii, and by the accidental union 
of A number ; and even those who are ignorant of 
these piindples. will acknowledge the superior effect 
which is obtained by the ciclusion of all other 
colours eicept those which harmonise with each 
o'hrr. 

In order to enable any person to find what colours 
hamiunisc with each other, the following table, which 
coAlains the harmonic colours, liaa l>ecn drawn up : 
Deepest Red .... Utue and Green equally mixed 

Ked Blue unmixed 

Omngc Red Blue mixed with much Indigo 

f Blue and Indizo. the IndijEO pre- 

^"^'^ 1 dominating 

Orange Yellow .. Indigo unmixed 
, .. / Violet and Indigo nearly iaeqoal 

\ portions 

Greenish Yellow . . Pale Violet 

Green Violet 

Greenish Blue .... Violet and Red in equal portions 

Blue Red 

Indiiro Orange Yellow 

\ ii-i- : Green. 

It appears from the preceding table that Blut 
barmoni^rs with Rett, or in other words, Red is laid 
V* be tlw: accidental colour of /?/rie, and eirc virm. 
s 



These ooloun are also called comptemtn^mTf \ 
because the one i« the complement of Utr 
what the other wants of white light ; that 
the two colours are aixed. ibey will alwajt' 
white by their combination. 

The followiQg gcnenl method of fiadioc tW 
muiiic colours will enable the nider to 
them for tints not coatftifled In Ihc pcaeodiiig 



Red 
Onuigr 



Yellow 



WVCB 



B1«e 



Indigo 



Tklet 



Let A B be the prismadc spectrum, conteiniiig off 
the colours in the proimrtion assigned to them bf 
Sir Isaac Newton. Bisect tlw spertnim nl tm, and 
let it be required to ascertain the colour which hsr- 
Bonises with the colour in the Indigo i^ptce at ;*. 
Take A m and set it from p \t» o, and the colour 
opposite o, or an orange yellow, will b? that which 
harmonises with the indigo ^ip. \t p is t>etwren 
'm and A, then the distance A m mubt be act oil 
(rum ffl towards B. 

In order to shew the method of oonstructiiig ob- 
ject plates on the preceding principle*, we shall 
suppose that the harmonic coloun of orange yellow 
and indigo arc to be employed. Four or live reKular 
figures, Hurh as those rdready deacribed, must be 
made out uf indigo coloured glass, some of them 
being plain, and others twisted. The same number 
of figures must also be made out of an orange yellow 
glass ; and some of these may be drawn of leu* 
diameter than othere, iu order that tints of varioiu 
intensities, but uf the same colour, may be obtained. 
Some of th&<te pieces of spun glass, of an iadife 
ooloor, may be intertwisted with fibres of the oringv 
yellow glass. A few pieces of white flint gloss, or 
crystal spun in a similar manner, and intertwisted, 
some with fibres of orange yellow, and others with 
fibres of indigo glass, shoi^d be added ; and whm 
nil these are joined to some fiat frogmrutx uf orange 
yellow glass, and indigo coloured glass, and plactid 
in the object plate, they will exhibit, when applied 
to the Kaleidoscope, the most chaste combinations 
of forms and coloora, which will not only delight 
the eye by the beauty of their outline, but also 1^ 
the t^erfvct biumonf ^ their tints. 



^iflect produced by ohjecU of anlr one colour 
kiptt rren ni))i>rior to the combination of two 
- m1.iiix«, in cotutructiag object plates of 
Loua fthailei of the Uktae colonr may be 
- t when lach objecU are mbted with 

oi Dqlourlwa gbua, twisted and epun, the 
aMe ud drlicaCe patCtims are produced ; and 

E which fuffirr pniu from the contain p la lion 
oolours, are able to look without nocaiii- 
a pattern in which there ia only one. 
nltf to shew the power of the inatramectf 
; extent to which tliece combinatious may be 
lone object pUte ba» been oonatructedf 
I sU(Ut of the magic lanthoni* in which com- 
ic of all the principal harmonic colours foU 
me aoothcr in flucceuion, and presented to 
• lenea of brilliaot Tiaioos no le«» ^raCifrin; 
MC suceesaioua of miuical suuniU from which 
derifea aach loteoic delight. 



KEW GALVANIC BATTERY. 




•DOf e ia a rough drawing of a Galvanic 
■hich I hare jtiKt constructed upon Ihe 
of Sinee, but which I think more simple 
rennait*, mure conrcuieut, and more 
nny other I have seen. To those of 
who may be dnirouii of poatesirin^ 
r. I have no bejQtation in saying that 
pfOVf highly salLfifiiclory ; 1 tht-relore feci 
in furniihiti; Ibeni with tbe necessary 
11 fur making one. 

) doz. 1 tS pot* (ordinary jelly 

^A mahogany stand, No. I, made with 

hold tbcm. The dirocntion? uf mine 

long, *Ji inulira wide, ubont 4 iiirhm 

hoard wiib lopporta about 4} iuchi*s 

pins ol racU end, ao that thtr lop may be 

nd off (iwily. Then procure 12 pieces of 

it^ nhnnt 2^ inches M^uare, and about the 

'HOC — half that ihickaesa would 

t*iiig thicker they are lew liable 

.^ome xinc plates, let them be 

ire. and about t inch thick, and 

!ii r uii the top board (tij;, 2), 



ao that I piece of xlnc bf Mh-er plntra in 

each pot (fig. 3). The ■ im should be 

good fttoat ones: thcf may uc m [it (as fig. 4), 
placed on the tops of the wires as ihcT come 
through tbe board, and screwed down with the bran 
balls A A. The conducting wires, or poles, may be 
bent in the form of a book (fig. 5), either savwed 
down, or made to touch the bruas balls only. The 
silver plates shonid be coaled with plaCina before 
oaing, which may be very easily done : procure 
some aulution uf platina (nitromoriate). a porom 
jar and tumbler, put the jar inaide the tumbler, fill 
it with dilute sulpharic acid, and outside of it in tbe 
tumbler ponr some dilute acid, as much aa will 
cover the silver plate, add a little of the aolution of 
platina ; then, in the poroiia jar immerse a piece of 
nnCf and in the tumbler the silver plate, connect 
tbcm together, when u riolent action will com- 
mence ; and, in a short time, the silver plate will 
be sofflciently covered as to be taken out and re- 
placed by another. Lastly, the sine platea should 
be well amalgamated with mercaryf taking car« not 
to let any get on the silver. 

To excite its action pour into each pot 2 ox. of 
sulphuric add (oil of vitriol), fill up with water, 
and immerse your pUtes. It will mointaiu its ac- 
tion for days together, if when the battery be done 
with the board be slipped off and iuuueraed in 
water. 

A great deal of trouble I consider !• tared by 
thia battery, and from its construction one or two, 
or tbe whole of tlie pota may ba used, which !■< not 
the case with the trough battery, as that is obliged 
to be whoUy charged. lu effeeta are astonishing, 
igniting a piece of stout Iron wire 6 inches in length. 

1. uoRSLHV, Chemist. 
Ryda, Isit of Wlgbt 



FLUID SUPPORT— SWIMMING. 

Tna human body, in an ordinary healthy state with 
the clieat full uf air, is lighter than water. 

If this truth were generally and familiarly under- 
stood, it would lead to the saving of more lives, in 
cases of shipwreck and in other accidents, than all 
the mechanical Ufe> preservers which man's inge- 
nuity will ever contrive. 

The human body with the chest fuU of air natu- 
rally floats with a bulk of about half the bead above 
the water, — having then no more tendency to sink 
than a log of fir. That a person in water, there- 
fore, may live and breathe, it is only neceatary to 
keep the face uppermost. The roaaon* that in orafi* 
nary accidents so many people are drowned who 
might eoiiily be saved, are chiefly the following :— 

Ut. They twlieve that the body is heavier than 
water, and therefore that continued eiertion is ne- 
cessary to keep it from finking ; and hence, instead 
of lying quietly on the back, witb the face upwarda, 
and vrith the face only out uf the water, they gene- 
rally aasuroe the position of a swimmer, in which 
tbe face ia downwards, and the whole head has to 
b« kept out of tbe water to allow of breathing. 
Now, OA a roan cannot retidn this position but by 
continued exerdon. he is soon exhausted, even if a 
swimmer, and if be is not. the unskilful attempt 
will scarcely secure for him even a few rr<ipiratiuiia. 
Tbe body raised for a moment by exertion above 
the natural level, sinks as fur below it when tbe 
exertion ceases ; and the plunge, by appearing the 



143 



MAGAZINE OF SCIKNCK. 



c4)miDcnc«iUFm of a pennuait sinldim. terrific* the 

unprocfiNctl iiidiiidital, and renders bitn an Miier 
victim tn his fate, — To conWncc a pcrsou learning 
to ivrim of the nutural buoyancy uf hU hoiiy, it iit 
« (;ood fiLtn to throw an teK i°to water about tivc 
f«ct dvcp, and then to dettiro biui to bring it up 
ngtUD. He disrnvcrs tliaL instead of his body with 
tbe chcBt full of air DAtunUly Kinking towards the 
v)!\:, hv has to Jo rre bis WHy itonnwurds. and is 
lifud a^ain by tbe water as louu as be ccasea hui 
effort. 

2d. 'nic7 fcftr that nater enterini; by tbe tara 
Biny dfuwti, aa if it eiitvred by tbe none ur mouth, 
■nd Ihey luAkc a fraiU'ful exertion of atrengtli to 
jirivpnt it; the Iniih hein^, bnncvcr, cbat it cao 
t-rity hll Ibc outer cnr, as tnr hs Uir membrane of 
tbe drum, where ild pn'^cnce is of no consequence. 
Kvcry diver nud swimiDer has his ears thus filled 
vitb ntter, and caret not. 

3d. Persons unaccustomed to the water, and in 
dauf^r of being dniwtir-d, grnerally attempt in their 
struggle to keep their bands above the aurfnce, from 
feeling H-^ if tlirir hands were imprisoned and n**tdcsB 
vbilt: bilow ; but this act is most hurtful, because 
any part nf tbe body held out of tbe water, in addi- 
tion to the face which must be out, requirea an 
effort tu flujtport it, which tbe individual ia supposed 
•t tlie time iU able to afford. 

4th. They do not rcilwt, that when a log of wood 
or a human body is floating upright, with a imall 
portion above the Burfai;c, in rough water, as at 
sea, i-rery wave in passing must cover it completely 
lor a little time, but will again leave ita top pro- 
jecting in the interval. Tbe practised awimmer 
cbuosra tbi« intcml for breathing. 

5th. They do not think of the importance of 
kt'eping tbe chest as full of air aa posaiblc ; the 
doing which hu nearly the name effect u tying a 
bladder of air to the neck, and, witliout other 
effort, will cause nearly the whole head* tc remain 
above ihe water. If the chest be ouce emptied, 
while from tlie face being under water the person 
munot inhale again, the body remains specifically 
heovicr than water, and will sink. 

When a man dives far, tbe pressure of deep 
wutL'r ccmpressea, or diminishes the bulk of tbe air 
in bis chest, so that without losing any of that air, 
he yet becomes really heavier than water, and would 
not again rise, hot for the exertion of swimming. 
Dr. Aniott mentions, that he once saw s sailor (a 
fioe-budied West India negro) fall into the calm sea 
from a yard<anu eighty feet high. Tlie velocity on 
bis reaching the water was so great, that he shot 
depp into it, and, of rourse, bis cbeft was com- 
preised aa now explainrd : probably also the shock 
stunned him, for altbuugh he was an exrellent swim- 
mer, he only moved his amis feebly ODoe or twice, 
end wo* tbcu seen gr aduoUy sinking for a long time 
afterwards, onlil he appeared only as a black and 
distant speck, descending towards the unknown re- 
gions of tbe abyss. 

Every person needs not lenm to swim ; but every 
one who makes voyipes should have practised the 
easy lesson of rrating in tbe water « ilh liie face ont. 
Tlic bead, from tbe lar^e quantity of bone in it, is a 
heavy part nf the body, yet. owing to its proximity 
to the chest, which ia eomparatively light, a Uitle 
action of adjustment with tbe hands easily kreps it 
uppermost; and there is an srcompanyiiig motion 
of the feet, culled Irttuliuy tl.p vahr, not di&cult 
to leani. which sufljcrh tu ^ti)4Ain the entire bead 
above Ihc surfsci'. M»iny ut liie seventy pas&rngeni 



who were sviiUowrd np on the 
Comet steam-boat near Orc<raock» fn 
1825, ndght have been saved by the 
soon wcut to their assistance, bad Lhey 
truth which we are now oploining 

A man having to swim for, may ocrastc 
nn his bank for a time, and resume bis Is 
be is souiewliat refreshed. 

So btlle is rcfjuircd to keep s swim 
above water, that many individuals, altof 
acquainted with what rcpirds snimming d 
have liten saved after ^hipi^reck, by cat4 
i4 a few floating ebipa or broken piecef 
An oar will sufiicc as a support to ha^ 
people^ provided no one of the atimber a 
it to keep more thin his bend out of Die < 
often, in cases where it might be thus s 
from each person wishing to have as ma 
security as possible, the number benefit^ 
lees than it might be. 

The most common contrivances, coOm 
serrers, for preventing drowning, are 
corks put rotmil the chest or neck, or air^ 
applied round the upper part of the body. 
when required by tljosc «tiu near thed 
into them through valved pipes. 

Ou the great rivers of China, where 
people find it more convenient to live t 
boats, than in houses upon the shore, Um 
children have a hollow boll of Mme ligM 
attached constantly to their necks, so thd 
frequent falls overboard they ore not in 

Life-boats have a large quantity of cork 
their structure, or of air-tight vessrla of d| 
or tin plate ; so that, even when the boats 
with water, a considerable part still floats, 
general nirfooe. 

Swimming is much easier to quadmpei 
man, because the ordinary motion of tbfl 
walking and running is that whieb 
them in swimming. Man ia at firat the 
less of creatures in water. A honne «l| 
mjng can carry bis rider with half the bo^ 
the water. Dogs commonly swim well a 
trial. — Swans, geese, and watcr.fowls l 
owing to the great thickness of fcathei 
under psrt of their bodies, and the great 
their lungs, and the hoUowness of their 
80 bulky and light, that they float upon 
like stately ships, moving tltemselres a 
webbed feet as oars. A water-fowl 
plumage half as balky as its nokixl body, 
half thai body above the surface of the 
similoily a man reclining on a floating ma 
nearly as much of his body shove the 1 
water-surface, as he forces of tlic ma 
His pojitiun, therefore, depends on the 
the mattress. 1 

A man walking in deep water moy 
sharp flints or broken glass with impuni^ 
his weight is nearly supported by tbe wall 

JJot many men have been drowned in I 
to wade aerass the fords of rivers, from 
that the body is so supported by the ^ 
does not press on the bottom sufficiently < 
sure footing against a very trifling cumot 
therefore, carrying a weight rm his brad, 
hands held over his head, as a solditf bi 
arms and knup&ock, may safely pass a il 
without a load, be «uidd be cai-ried 
»>tream. 



MAGAZINE OP SCIENCE. 



U3 



■Uw! in Cliln« ofcathinf; 

that l!w catclier be wi-II 

ui.t Kri^Jn bring firvt gtrenci 

watrr to tempt tlit^m, a man 

Ist of it, under whot ippf ara 

bfivlitrt drifting with the fttrcarn, and 

approscbea find finrrounds lihn, he 

)Ca1iu a ricK booty by »nntching tlie crea- 

by one — adroftiy nmking thetn dis- 

r were diriog. and thcD seccring them 

Emch bird beoomcfl an ■ piece of cork at- 

oge their ipecific gravity, by dimi- 

ng the td<e of a little nir>bug 

their body. It is because this bag i$ 

rd* tlie ucdcr side of the body, Uiat a 

ts irilh the bcUy uppermost. 

t, ID aader]^ng the process of 

t mnrb oerifomi matter. Hence 

$ drowned and remaining in the 

swell after a time, and rise to the 

to Biak when the stiU inercaiing quan- 

11 burst the cOHtiuniug pnrbt. 

' sinks to the same depth whether 
supporting it be great or small : — 
a pnrL*el.nn ba^in i? placed first in a 
in a second bii«ih oi.ty so iiiULh largir 
that n »]wx)nful or two of water Bufficeo to 
interral Itetwecn them. One ounce of 
le Utter way may float a thing weighing a 
tnore, exhibiting another instance of the 
paradox : — And if the largest ship of 
rceived into o dock, or ca>e, so exactly 
hat there were ouly hnlf an inch of interval 
and the wall or side of the containing 
would rtoiit as corapletily, when the few 
lof wnier recjuired to fiUthb little inteml 
water-mark were pcured iji, as if it 
te bigb ttta. I n some caital luckn, ibe boats 
•pace iu which they liave to rife and fall, 
le expense of wuter ut the lock Is dlmi- 

mding examples of floating arv all illns- 
o of the trnlh that the presBurc of • fluid 
BMrwd body ia exactly propurlioned to the 

It of the surface pri-sse<l U|Kin. The 
I juct balanoe one another, and the 
t has to be balanced by the weight of 

TING OF METALLIC ORES. 
(Jtetumtif from page \2Q.J 

epj— As most of the lead orex contain 
bur or areenie, tht->y n-quiie to be well 

Taice A (|iiiiilal of rnnictA^d ore, with the 

ttity of calcini'd borax, h^ilf a qaititnl of 
Td glass, a qinrtcr ol n quinTal of pitch, 
ih clean iron lilitiei''. Line the crucible 

id charcoal dust, and put the mixtun: into 

le» and place it be/ort: the hrllawa of a 
When it U red hot. nii^e the Are for 

Nrmty miiintes, tjien withdraw the cnici- 

mk It when cold. 

kimid teay. — Dissolve the ore by boiling 
ntrroos acid ; the sulphur, insoluhle stony 

""nalx o{ iron »t11 remain. The iron may 
l)y d;£;e»tion, in the marine uniS, iind 
by digeslioo, In caustic fixed olbili. 



The nitrous solution contains the lead onil silver, 
v»hieh should be prcci|iitated by liit; niinrral filed 

alkali, and the precipitnie well wjsht t' : ' ' r, 

dried, and writhed. Digest it in i k- 

alketU, which will take up the calx :■: Iu: 

residuum being again dried and weighed, gives tJic 
proportion of the calx of lead, 132 grains of which 
arc equal to lOU of lead in its metallic stat«. The 
difference of wrii;ht of the precipitate before and 
after the application of the volatite alkali, gives the 
quantity of silver, 129 grains of which are equal to 
100 of eilver in ita metallic state. 

Copper Oret. — Take an exact troy ounce of the 
ore, previously pulverized, and calcine tt well ; stir 
it all the time with an iron rod, without removing it 
from the crodble ; after the calcination add an equal 
quantity of borax, half the quantity of fusible glass, 
oiie-fourtli Uie quantity of pitch, and a little char- 
coal-dutit ; rub the inner sorfaiT of the crucible, 
with a paste composed of charcoaUdust, a little fino 
powdered clay, and water. Cover the mass with 
common salt, and put a lid on the crucible, which 
is to be placed in a fnmni*e : the firr is to be raised 
lErsdually, till it borus briskly, and the crucible con. 
tinued Lu it for half an hour, stirring tlic uictiU fre- 
quently with an iron rod, and v^cn the scoria whicii 
adheres to the rod appears clear, then the cniciLle 
must be taken out, and auflfored to cool t after which 
it must be broken, and the regulna separuted and 
weighed ; this ii catleil black copper, to refine *hicb, 
eqnal parts of commou salt and nitre are to be well 
mixed together. The black copper is brought into 
fudon, and a tea-«poouful of the flux is thronn upon 
it, which is repeated three or four times, when the 
metal is poured iolo on ingot mould, and the button 
is found to be Aoe copper. 

In the humid way. — Make a solution of Tltreotu 
copper ore, in five times ita weight of concentrated 
viinulic acid, and boil it to dryness ; add as much 
water as will dissolve the vitriol tlma formed ; to 
this solution add a cleftn bar of iron, which vrill 
precipitate the whole of the copper in its metallic 
form. If the solution be contaminated with iron, 
the copper must be re-dissolved in the same manoer, 
and precipitated ogain. The aolphnr may be aepa- 
rotcd by filtration, 

Dumutfi OrrM. — If the ore be iniuerTdizird by sul- 
phor, or eulphur and iron, a pri'vious roasting will 
be nef«s*ary. The strong ons itrjuirc no rousting, 
bat only to be reduced to a ftne powder. Take the 
assay weight and mix it with half the <|uantity of 
calcined borax, and the same of pounded gloKs ; line 
the crucible with charcoal; melc it as quickly as 
possible ; and vhen well dune, take out the crucibl«« 
and let it cool gradually. The regolui will be found 
at the bottom. 

In the tiumid tcay. — Bismuth is easily soluble i« 
nitrous acid or uiua-regia. Ita solution is colour- 
less, and is precipitable by the addition of pure 
water; 118 grains of the precipitate from niuotu 
acid well washed and dried, are equal to 100 of bis- 
muth in ita metallic form. 

Aiiiimoniai Ores. — Take a common cmcible, bore 
a numbiT of »umlt hole* iu the bottom, and place iu 
it another crucible a sixe smaller, luting thun well 
together, then put llic proper quantity of ore in 
small lumps into the upper crueihle, oitd lute thereon 
a cover ; place these vessels on a hearth, and sur- 
round tliem with f tones nlwut six inches distant from 
them ; the intermediate space must be filled with 
ashes, so tluittbcundermo«tcr«ciblemaybcooveird 
with them ; but opon the upper charcMl most b* 



144 



MAGAZINB OF SCIENCE. 



loid, and the whulc maAr red hot by the ajmstance 
of b«nd-bcUowt. Tlic anliinooy Ixfin^ of i>:Lsy fiuion 
is Mparutcd, and ruiia through the holeft of the 
Tipper veiBcl into the inferior ooe, where it is col- 
lected . 

Humid Auay of Arttniaied Aniimonif. — Dis- 
solve the ore in nqiin'regin, both the rc^oilaa sad 
arveiitL' remnin in the soluCioo, the sitlphur in flepa<- 
mttvl by filtration. If the solation be boiled with 
twice its weight of strong nitrous acid, the regulns 
<]f antimony wiU be precipitat^^d, aitd the ar»emc 
conrerted into tn acid, which may be obtained by 
enporatien to drjncM. 

Mangnntat Orr. — The regulua U obtoioed by 
mixing tilt! call or ore of muouanctir vith pitch, 
niaViag it into o boll, and putting it into a crucible, 
lined with powdered charcoal, one-tentb of an inch 
on the Aided, aad one-fourth of an inch at bottoLn. 
then filling the empty space with chiircoul dual, 
covering the crucible with nnutlirr inverted aiid 
luted on, and exposing it to the strangest heat of a 
furicc fnr an hour or more. 

In the humid tray, — The ores should be firat well 
rofiKtcd to deplUoKisticate the oabt of mangaucfte 
and iron, if aoy, And then trentcd with nitrous arid 
Co dissolve the earths. Tlie residuum shoukt now 
be treated with nitroua acid and sugar, by which 
means a colourless solution of manguuese will b« 
■obtained, and UVcniae of the iron, if any. Precipi- 
tate with tlic Frussiau alkali, and digest the pre- 
ctpitfile in pure water ; the pnis»iatt; of mangnitese 
will be dissolved, whilst the pmsaitite of iron will 
remain undiswlred. 

Anenicat Otm, — This anay is made by rablima- 
tion in clove ve«seU. Beat the ore into small pieces, 
aitd put them into a mutra<», which place in a sand- 
1>ot, with a proper dcgrvc of heat ; the arsenic sub- 
Ittiiefc in thifc operation, and adheres to the upper 
piirt of the ^c^ficl; when il must be carefully coU 
li-cted with a view to nscrrtaiii its weight. Somc- 
ttmes a single sublimation will not be suffioieot, for 
the arstiuic in raany cases will melt with the ore, 
and prevent Its total volntilizadoD ; in which ctue it 
is better to perform the first Bubtimotiuu with a 
moderate heat, and afterwards bruise tlie remainder 
iigala, and expose it to a stronger heat. 

In the humid iray. — Digest the ore in marine 
acid, nddiiie the nitrous by de^ecs to help the 
solution. The sulphur will be found un xhc. filter ; 
the arsenic will rvuiatn in ihc «uluiioi], and may be 
precipitated in its rociallic I'umi by zinc, adduig 
spirit of wine to the aulution. 

Nickel Ore. — The ores must be well roasted to 
expel the sulphur and arseuic ; the greener the calx 
proves during this torrcfactiun, tlie more it abounds 
in ilie nickel ; but the redder it is, the more iron it 
rootHins. The proper qiiunttty of this roastt'd ore 
is fused in an open crucible, with twice or thrice its 
Wright of bUck Hux, and the whole covered with 
common salt. By expofing the crucible to the 
strijngrft hcnt of a forge-6re, and making the fusion 
compietc, a rcgulus will be produced. This rcgulos 
i» out pure, but contains a portion of arsenic, oobalt» 
oud iron. Of the first it may he deprived by a 
(rcsh calcination, with the addirion of powdered 
chaivodl ; and of the second by scorification ; but it 
is With difficulty that it is entirely freed from the 
iriin. 

Jh the Mtmid way. — By solntlon In nitrous acid, 
it la freed from its sulphur; and by adding water to 
UieaolutioQ, bismuth, if any, may be precipitated; 



a£ may silver, if contained tn it, by the lotristc 
and CA)ppcr, wlwn any, by iron. 

Tn- separate cobalt from nick»*l, when the 
'u in conaidermble quantity, drop a saturated 
tion nf the roasted ore in nitroua arid into ht 
volatile alkalt; the cobaltic part is instantly 
dissolved, and assumes a garnet colour ; when 61 
ed, a grey powder remains on the fitt£r, which 
the nickel. ']*he cobalt mtiy be precipitated fr 
the volatile alkali by snr acid. 

(To be eoiUmi»Hi.J 



M1SCELI.ANIES. 

Oh the lif/ht tlepehjied at the repmviiott 
racie Aeith into frtt'jmettt*, — M. Dunutf hM^ 

served that the borocic acid, when melted, prvwaid 
Q particular phenomenon at the moment uf its coala 
ing. When it is cooled in a plattna di»Ij, 
instanf when the contractions of the two n 
becomes unequal, the boracic acid aplib 
charges a bright light, which follows the i 
of the cracks. This light, which is probsM 
to the cause which do^lopes the opposite 
ties in plates of mica quickly »t:pflrBted. 
ficicnily strong to be seen in the day-time. I be 
experiment is a remarkable one in the ilark. — Auu 
de ChiiH. p. 324, 335. 

To C7ean £00/ Toju, Parchment, Sfc. — ^The fol- 
lowing mixture will readily take out grease, ink 
spots, and the stains oocaaianed by the juice of flhui, 
red port wine, &c. from all leather or parchment. 
Mix in a phial 1 drnchm oxymuriate of potash, with 
2 ounces of distilled water, and when Che sidt is 
dissolved, add 2 ounces of muriatic acid. Then 
shskit^ well together iu another phial. 3 ouneea of 
rerttficd spirit of wine, and half an oonce of escen- 
tial oil of lemon ; unite the contents of the two 
pbialb, and keep the liqmd tlins prepared closely 
corked for use. This chemical liquid should be ap- 
plied with a clean sponge, and dried id a gentle beal. 
The boot tops mny be poUiibed with a proper brush* 
so as to appear like new leather. < 

Method of Preparing Quill*. — The folkMring is 
the manner in which M. Scholz of Vienna proceed! 
ill the preparation of quills for writing^, by means 
of which he renders them more durable, and even 
superior tn the beat Hamburgh quilU. Fur this 
purpose he makes use of s kettle, into which he 
pourx common water, so as to ocxrupy the fourth 
part of it£ capacity, he then suspends a certam 
quantity of feathers perpendicularly, the barrel 
lowermost, and m placed, as Uiat its extremity may 
uhty touch the surface oi the water ; he then conn 
tht' kettle with a lid proprrlr adjusted, boils Che 
water, and keeps tlie feathers four hours in this 
vapour bath. By uieAus nf tliis process be frees 
them of their fatty parts, and renders tbrm soft and 
transparent. On the following day, after having 
scraped them with the blade of a knife, and then 
rubbed them with a bit of cloth, be expo«e& them 
to a moderate heat ; by the day after thf.y arv per- 
fectly bard and transparent, without however havio^ 
the inconvenience of splitting too eu»ily. 

PhiHtpharic Oil. — Put one part of phosphorus to 
six paru of olive oil. Set the phial for a time in a 
warm place — for example, a ba&in of warm waters 
when they will unite, and form a luminous and 
harmless fluid. The phiol must always be corked 
when not in u^. 



l«XM>x.— PIUifLilbj D. rftA]icu,«. WhlU) ItorK Lane. MUsEmL— Pubiuhadby W. Bamuy, II, pataraMler 




ON PRICKING ORGAN BARRELS. 

TwB art of pricking orxui barreU UcoDfined to few 
hudf, the operation is very simple, but requires 
very great fttteotiun, both in the miirking and the 
pinning the barrel. The marking i* i»crfonnc<t by 
nieaiii of a 6Bt diTiding pUtf, about 18 incbee 
diazneter. The pUte has upon ic a number ol 
gimqw of h ooncealric cirdea, each poup of circlci 
being dinded into a certain nnaiber of equal p&rta 
or bara, (see Pig. 2.) Theac diviiioni arc snb- 
divided one circle (tec Fig. 3) into four parti for 
eommon time, the next into six for compound com- 
mon time ; tbc third into three parts for triple time, 
and the fourth into oine paru for compound triple 
lime. The wheel being thna prepared, and the bar- 
rel being covered with white paper, or painted blue, 
proceed to prick it thos : — Place the barrel in the 
urKau to which it fiU, the axift uf the barrel being 
Icnpthened, iti order that the wheel may be fastened 
to it by a binding screw. (The- wheel is seen at- 
tached to the barrel in Fig. 1.) Thus the wheel and 
barrel turn round together. Then count the number 
of bars in the tune to be pricked, and find what 
group of circlea agrees with that numbrr, and which 
circle of that group' agrers with the time of the 
tunc. The drcle to work from binnf? thus determiucd, 
Ax to the organ a piece of poiiiti-d wire, or a strip of 
brass like a clock-hand ; so that when the wheel turns 
the wire may remain fixed, aud lo as just to touch 
<»r pass across the required circle. Every thing 
being now prepared, begin by ruling a straight line 
•long the barrel ; aud baring the written music be- 
fore yon, mark the first tum ^ givteg i. Iiy **^ ■ 
itammer to the small lever, which b cormected with 
the pipe representing that aoU; tUs of coarse will 
make a &mall mark on tbo barrel. Iben turn the 
•wheel until the wire sho^ that it has trardled t 
«pace equid to the length flf the nc^e. Nnw stop, 
and give the same lever Mvother • ■ 
the two little marks thus iMde by /« 
pen and ink. which will give the K-ugm in.i =aua. 
tion of the staple required afterwarda to l>e driven 
in : thus proceed until tb« whole tone be coraplrt*. 
The pins and staples arc «ftcrwards tn be pnt in i 
ihey are made of Battened wire, bent to their pro- 
per sise writh plycrs ; thu^ when the circle of the 
barrel is complete, the tuQC will be complete also. 
It should have been obH-rrrd, that thr ktraight line 
upon the barrd sfaonld ho medr nxactly at the part 
wbare the leven touch it. when the fixed win- 
points at the straight line shown opon Fig. 2, and 
that line is to be eonKidered as the begfinning of the 
first bar of the tunc. \lao. to ke«5p the hsmel 
steady during the prirking of it, care most be taken 
to fix it by the usual etop at the owl of the organ, 
as is done when die organ is pkyad. 'Wore not this 
carefntly attended to the various pins would be opt 
to deviate from a rinht line, confusion being thereby 
oecasiooed. One tnne taking up but a single line 
to each note, and these line* occupying but about a 
tenth uf an Inch in width, there is usually room for 
•wernl tunes ujKin tlie same bsrrel. A lecond, and 
afterwards other lunes moy, therefore, be pricked in 
the same manner, shifting the barrel a trifling degree 
sideways, so that the hammers may occupy a dif- 
ferent portion of the surface. 

To render clearer the op«nlioa take the foUow- 
ia^ cxamjUe : — 



titlCt 

>tba 



which, it will be seen, is the first portion of 
tTme, ** The blue bcUs of Scotland." Couotinf 
bars in the tuna we ind there arc 16, (oi 
ballads and danoea vary from 16 bars to 
have always an even number) ; therefore lool 
the wheel for that circle with 16 divisions— wbi 
the inner one. As the tunc is in common time, ^ 
must look for the space belonging to that group 
circles which h divided into fonr parts; tl 
be fuund the innermost space: it is thai, tbci 
which we are to work from. Now, it will be 
that the tune b^ns with an imperfect bar. or 
whifii oont^nt only a crotchet ; the due tijuc 
will be made up at the cod of the tune ; it n 
therefore, at first neglcrted, and the p; 
begun at the next bar. Fu the barrel 
their proper places, adjust the stop at 
keep the barrel steady, and turn the han 
move the barrel round until the pointer 
with the straight line marked down the wheel ; 
keep it steady. Ascertain (which should be 
beforehand in chalk, marking each with the 
of the DOte.) which of the hanunerv Hprem wii 
DoU B wanted, and fcive it a slight tap, it wiU of 
courM make an indent upon the barrel; at that 
mark a straight line is to be made finm end to cad 
of the barrel, that ail the other tunet may be bcfO 
at the same spot, and also that the player may know 
the commencement of each tune, not being sub- 
jected to the awkwardness of commendng to plaf 
in the middle of a tune. Supposing, then, that th« 
barrel baa been shifted, in order to make that mark, 
it muit be reatorad wadAy to the same place, again 
the point of the hammer touching the mark it 
previously made, Now turn the wheel and * 
br its uMial bandk, until the pointer shows 
whcfll to have pancd offer tvo spaces, that 
the length of the minim E in the tune, tap the 
hammer again, and join the marks it hoa now 
to the former by a line in ink. Before moving tibt 
burel i^io give V a tap, then turn the barrri 
OM space equal to the iM^tb uf the crotchet D, and 
give a second tap ; join these two marks as before, 
otid Ktrike C the next note ; turn the wheel ov 
space, and strike C again ; join the two marks, snd 
strike B the fir«t note of the next bar. This being 
i minim requires /wo spaoas to be passed, when it 
is itrut^k again, and the tvo marks joined as before ) 
the next note C is nade as in the former C. T« 
make up the time of the bar are two quaven D 
E, ihc«r nxiuire only half a fpace la length : ttan 
other notes arc to be noarked in the some mannvi 
Where a dot is placed after a note it mult be hal 
as long sgntn. M'here a rest occurs, as at the en 
of the example, a proportional interval nuit b( 
passed over before the next note is itmck. Whcr 
(he music is Miaccato a very small infaerral is al]ow«i 
between one note and another — which prevnta thi 
notes being so intimately blended together nt ii 
ordinary ctrcumstanceo. In imitating the MMBd fl 
bcUs this is to be observed. 

The appoffiatura, tht/vpe, and rariona af tb 
other graces or omamenta introduced into ficoea « 
music, may be imitated with ease by any persern i 
common ingenoity. The flats and sharps have pip< 
and hammen appropriated to them. Am • sAair 



thn 



MAGA2IN£ OF SCIENCE, 



147 



<d two DOt«« ftoundcd in quick inccrtsion 
y, it ni«y be made by marking tGc 
te Ikelr lenstb lu before : but instmd of 
Abm fftaples to product connected 
each, they must be prickrd with 6nc 
, with I roioute internl between uch, 
to havo the }iui» of the one DOte exnt-tly 
te between tboae of the other, that a 
of toe two loaud* may be produced. 
crmt cfTeft of strength and toflneas of 
fgrt« and piano, ii seldom imitated in 
: hot in tlir best imttniaicnts it is a 
portont feature, it may be produced 
Or ratliur the dej^ree of prominence of 
If. (br eiample. a long staple, repre- 
srmibreve, and whicb we will suppose an 
b, be inserted at an equal height from 
of lh« barrel at both of its ends, it of 
d lift up the hammer and valve ett&ehed 
y all alon^. nnd thf fnund produced would 
> ".f..,*,ty; but if the staple be hiflter 
other, the mund would of course 
< , on account of the tbItc admtt- 
tifns mora wind to the pipes than at 

iMa nvertures, and other long pieces of 
t priehed tip<m the barrels of organs. No 
of the method of proceeding is to be 
The slight TariotiDn being in tlio stop 
I, which in the ctse of ordinary tunes ii 
El cQta or channels into which a brass stop 
lowing the barrel to torn round, but not to 
Brftlly : bat in a barrel prepared for an 
the stop is mode of a s«rew, so that the 
h baa made one revolution, has Abo 
one thread of the screw, whereby 
of the hammers take hold of a different 
•tBples. In playing an orerture it Is to be 
~, that when completed the player most 
ahifl the barrel to Ito original position 
mencing it. 
--Tbe barrels of organs are always made of 
nider wood, which ut-vcr splits, and allows 
to be drircD in ea^iily. The flnttcned 
and crery other similar material, both 
of the musical instrument maker and 
may be purchased of a person who 
Long Acre, in Drury Lnne, Ijondon. 
wire cosu about 38. per A, and 1 Tb will 
many tune*. 



HSPARATION OF PIGMENTS. 
fBmtmtdfrom pcg^ 136 J 



— ^These snbeUncea are " hydrates of 
ngmfiea, that they are composed of 
of iron, mixed in Tarious propor- 
dotcly combined with Tarious 

proportion of clay, the brighter 
when there is a portion of clay, 
feala greasy to the touch, ai^ has 
than Ihoae have which are mixed with 

ochrm become red by calcination : the 
I, when pure, prmince the finest red. 
of m." which is tnconroctly spelled 
"me,** takes ita etymology from 



the old word m (misaeau), a rimlcC or brooks 
probably because that this ochre was Aniad deposited 
in places formed in brooks of fprmginouii wnt«r*. 

Exposed to the fire, this substance takes a reddish 
brown color, not so bnUtant, as (hit of the oxide 
of iron. This fact proves that it contaia<« Home 
remaina of vegetable substances, or bituniaona 
matter. 

Terra di Sienna is a browa ochre, wblrh» hy 
calcination, prodnres only a noderntely strong red. 
This proves that It must contain subfitanoes whirh 
prevent the development of the Tiolet color, which 
belongs to the oxide of imn in its pure state. 

Ochres nisy be prepared artiftciolly, by raoisteuing 
the ruit of iron, and prertpitating by the alktiHs, 
Rolations of this metal. For instance, in precipi- 
tating it by the snb'Carbonite of soda, or of muriate 
of potass, of nitrate, of acetate of iron, or persulphate 
of iron, the most brilliiint brown ochres are obtained. 
If the sulphate of iron is of a low oxidalioa, the 
precipitate is olive-colored, bat it soon becomes 
TcUow at the surface by absorbing a greater quantity 
of oxygen. To extend this operation to all the 
precipitstes, it only requires exposun; to the air, by 
stirring it up for a safRcient time. The same thing 
may be obtained in winter quite easily, by exposing 
it to the action of frost in wide shallow pans : the 
water pussing into the rtate of ice, leaves a smsll 
qQruitit7 of air dispngfiged, which unites with the 
prrctpiute, and is sufficient to give it an even 
yellow tone. 

When bright ochrea arc reqolred, it will be ne- 
cewary to mix alum, in certain proportiuni with 
sulphate of iron ; the solutionis then to beprecipi* 
tated by Umc water. There exist in the natural 
state orhrrs of so very fine a qiuJity, that Ihcy re- 
quire no otbirr preparation than that of licing 
wsahed : therefore it is scarcely worth while to 
manufacture them artificially. 

The wrrmanency of these eolors is proved by the 
atabe of the old pictures. In a box of colors found 
at Pompeii, and analysed by M. Count Chaptal, he 
discovered yellow ochre purified by washing, which 
had preserved Its originnl brightness. 

Orpiment. — This color was known in ancient 
tioMs ; the lAtina called it auripigmenturo, (gold 
color,) whence, by corruption, ita present name la 
derived. It is a sulphnrrt of arsenic, found per- 
fecily formed in a natural state : it is also preparetl 
by Artificial means. 

There are two kinds of snlphuret of arsenic, the 
reaajta of diflerent proportions of these substancet 
in combination. If the sulphur should predominate, 
tbe product will be a clear and very brilliant yellow ; 
hut should the arsenic predominate, the color will 
be orange ; and it ia then called " red orpiment," 
or *' re-algar." 

Both these species hare been in nse from the 
earliest times of painting ; and it is easy to perceive 
that Chia color must not be mixed with white lead, 
nor with any of those colors Into which lea4l enters, 
auchas nnusicot, minium, muriate and chromate of 
lead, and Naples yellow. 

The sulphur in combination with the araeiUc, 
having leas affinity with this metal than for lead, 
lets it go, and forms a snlphuret of lead of a dark 
greyish color. But orpiment may be employed 
alone, or with ochres, and other colon that do not 
actupon them, as tern* verte and ultramarine, TTicre 
is little doubt but that the brilliant yellows, which 
we see in some ancient picturee, are prcparaUona oi 
orpiment. 



1 



MAGAZINE OF SCIENCE. 



Red orpitnent, u wn bIiiII ihow in ita place, ii 
not «> pcrmnnmt ■« thr yellow BCrt. 

SuIpAyret of Cadmivm. — ChcmuU wlio have 
prepared this color 8«y tlut it Anrt nnt cluingr. I 
•m not, however, iiwire whether it han l>ecn uwd in 
OOmbinatioQ with wbit« lead. I fear lli»t in larli a 
cue the sulphur wnuld quit the cadmium, to unite 
with the lead. If that sboold not happen, tbia 
wotthl be a moat naeful diacovery. tt is to be re- 
groCted that at present cadmiam is scarce; but it is 
to br hoped, that u chromatc of iron haslietrndia- 
ooTcred. we aball be equally fortunate with respect 
to (hill article. 

We are auored that the sulpfanrct of cadmium is 
Wtd. in Germany ; and it is to be bad in Paris 
•mcmgfit the princip«l manufacturing chemistA. 

(7h fo conimued.) 



MANUFACTURE OF MARBLES, BULLETS, 
AND SHOT. 

Lakck qnantities of lead are used in this country 
in the manufacture of ahot and buUfts. ko diH- 
tioguished as tlie spherical masses are hmall ur larxe. 
There are three conrcnient methods of prodncing 
shot — rolling, casting, and granulation : the Arst is 
but little resortnl to in the sense here intended ; 
the second operation is that by means of which the 
mott perfet^t buUetii are ^enenilly obtwned : and 
the third, in that by which tlic shot of rommcrcr is 
produced. If lead be drawn out into square strips 
or wire, and then be cut up, by means of a Icoife, 
or by any other instmment, into little cubical- 
sections, these may be placed, several scores to- 
gether, between two flat stones, the undermost one 
lying 6nn, and the upper one admitting of btdng 
moved about in every direction, and thus rolled into 
perfect shot. To secure exact sphericity, the scone 
Binst be moved in a sort of epicycloidoi curve ; for 
if it be advanced in right lines, or were merely spaa 
round, the shot wotOd have a cylindrical figure : 
iron plates, or polished stones, may be used to give 
to the shot a smoother and brighter appearance. It 
ia in the above method tbnt hoys' marbles are made ; 
and considering with what truth they are turned out 
of hnud, it will show that the method is not to be 
condemned, except for its greater tcdiousness. It 
was by a method anatogouE to the foregoing, that 
small shot was originaUy manufactured : rubes of 
lead may likewise have an im|>erfect spherical form 
given to them by shaking them together. We 
KOoUeot this method being once rnmcd to ingenious 
BCCQont by two country fursemrn, who were in the 
Kal^t of shooting great numbers of the wild ducks 
which frequented the mill dam : the men used, in 
the first place, to cut up the lead into angular bits 
of the desired sixe ; these they put into an oblong 
can of sheet-iron, which they fastened to the edge 
of the forge hammer ; the latter, by its motion, 
vidlcntly shook the conteals of the can up and 
down, until the bits within, striking o^nst each 
other in every direction, soon became a very 
efficient, though not very handsome, sort of dock 
shot. 

Pistol bullets and rifle bolls, requiring to be of 
exact else, are generally cast in moulds, one at a 
time : swsn shot, •and other like sorts, ore cost iu 
a similar msnner, but icfcraj together. 



The annesrd cut represents a pair of 
for cuting swan shot. Thoy conustof twni 




A B. about ten inches long each, made of 
and joined by a pin at the end, much iu the 
of a pair of common nut-cracks; in the 
upper parts, which arc made to dose terj 
corresponding Itemiisphcrical caritiea are 
having each a little outlet to the edge. When 
moutiL are closed for casting, the stsel plate C | 
bt-ou^ht over the face until it rests against a pin «{ 
D ; its row of counter-sunk perforutioos exactlj 
lying over the boles in the sides. Melted lead i 
now ponred into each hollow through the apertaraj 
in the plate ; after which, by striking or prenmg J 
on the port at £, the costablea, or tails, of them 
are cnt off, and the shot taken out of the moold. I 
Notwithstanding the generally received opinioM 
that one principal feature of perfection in a buUeC j 
sphericity, Mr. J. W. Bo«weU, in an inge&ioQi oral 
munication to the Repertory of Arts, reciowssdj 
the use of balls of the foregoing Agnm, Fig. «, i 
OS better adapted to move in a strsight line througl 
the air, than those of a globular form, and whid 
oeceasarily assume a rotatury motion in their proi 
* gress through the barrel of the piece, and comm, 

3uently take a Inas in their projectile dir«ctiM{ 
etermined by their friction against the right haai 
side, the left hand nde, or the bottom of the band 
The vrr iter of the pi*per referred to, and who^ 
theoretical obs crvatior.s arc too long for qnotBtioi| 
says, " 1 nevrr, before these experiments, prmctiMl 
shooting at a mark ; and yet, with these bnUalaJ 
from a common pistol, 1 hane often hit a mark si 
inches square, at fourteen yards' dhttance, in t] 
proportion of seven times oct of twelve shots, vhi 
1 could not, at the saine time, with common baUl 
from the same pistol, hit it ufteiir^r than onoe in td 
times." Any gentleman disposed to try bullets « 
these forms, might easily cast a few for expertmesi 
from well-dried plaster of Paris mouhb, if bm 
ones coutd not be easily obtained. 

The smaUer sorts of shot are mannfaetured in I 
very perfect manner by gninulution, or pouring tb 
metal from a considerable heisht, in consequence e 
which it separates into globnlar mssscs of differen 
sizes, which mol into that form during their desoenf 
sod which cooling is completed by th«ir falling inn 
water. One of the earlieit successful practitcn fli 
this method wrs an individual at Bristol, of tbi 
name of Watts, a plumber, who, in 1782, obtaioe( 
a patent for " omenated shot;" the material d 
wlUck coosisted of soft pig lead sscnrated with «bil| 
or ycUow arsenic, in the proportion of about fortj 
pounds of the Utter to twenty hundred weight fl 
the former. To effect the mixture, the lead, aloq) 
with the arsenic, was put into an iron pot cload] 
covered, and then heated to redness ; this potaonaj 
lead was not ut>ed lilone, but mixed in various proi 




MAGAZINE OF SC1£NC£. 



140 



lass vtth lb«t tntdnded for the making of .abot. 
iptiiil rifbt baring loDf since eipired, mo«t of 
■Ot oov •een b made of lead hariDg in it aome 
■■ if mmaSe^ by wbicb its rpbericitj and woiu 
m Smprored. To obviate objectiont wbicb 
lw«« made against the anenatcd material, b 

^[OBntity of quickstlver baa been miied with 
wd, and wbkh answen tbc porpose lufficientlj. 
blkrwinf aeconDt has been giren of the inven- 
tf t±e patent sbot by Watti. In otmseqamce 
^nmm, the idea waa oonccdTcd of poiuing 
d laid through a coniiderable apace i and the 
taaCBt mt Ihed from the tower of the church 
, Mary GEcddiffe, the church immortaliaed by 
srtoa the poet. Watts is said to bare lold big 
t to the eminent bouse of Walkers, Moltby, 
ir. and Co. for jflO.OOO. With this mm, be 
■ed to boiM ■ crescent at Clifton : the situa- 
was a huge rock, nnd the whole mm 
ia making excavations, and in raising 
walls for Foandaliuuv, which long bore the 

of WatU's Folly, and upon which walla Tra- 
I flflse waa afterwards erected. 




e specification of the patent obtained by the 
ibore named is inserted in the third Tolome of 
Icpertofyof Aru, from which work it ia here 
oribed, along with the accompanying Tertical 
m* of the kind of building commonly used in 
nntuhcturr of shot. Moit nsitera to London 
noticed the shot towers uu the banks of the 
: theae are on the Hiutb side of the rirer ; 
tbt ia about 150 feet* lifording a full nf 




abont 1 30 feet for the shot. The alloy is deaoribed, 
in the apedfication, as cooaisttng of forty |>oviida of 
aiTCnic to a ton of lesd. prepared ai above stated* 
and cast into pi^ to be ready for u8«. By meant 
of a suitable tackle and chain, — a part only of 
which, to prevent conrosion in the drawing, ia 
brought into view at a a, — ten pigs, of about I^ 
cwt. each, are drawn up through a trap-door into 
the melting-room at the to^i of the tower ; here the 
pigs are aoooeasively put into the caaldron b, whiofa 
is heated by a common furnace, e, beneath, haviuff 
a brick floe and chimney, terminated by an iron 
funnel ^^acbi^g to the top of the upper dom«, or 
lantern- When the alloy is melted, sod the soiria 
property formed, a portion of the latter ii ladled by 
the roelter into a kind of square colander, d, sup- 
ported in an iron frame titcd dose to the fumaoa g 
this vrasel is twelve or fourtwn inches aquare ; it 
has a handle like^a frying pan, and its bottom ia 
perforated with circular holes, of a site salted to 
the shot About to be made. The quantity of drooa 
required being determined by the experiment of 
making a few shot (wbicli are not auffered to descend 
below the floor of the melting-room), a man now 
ladles the fluid metal out of the cauldron into the 
perforated vessel ; in ronniog through which it ia 
somewhat detained and cooled in paasing the looriaf 
which teudi to Reparate It in small portiona, where 
it collects underneath the colander at every h<Ae In 
■mall globules, which instantly drop, and are fol- 
lowed by other globular in such rapid Hucreaaiun at 
to appear at a little distauce like a pouring rain of 
liquid silver. This m«t4dUc ihower is rrpreseotod 
in the cut tee, and falls into a large tub of water,^ 
placed underneath. From the great specific gravity 
of the sbot, they do not scatter in their desoent ( 
and the workmen croas the bottom floor of the 
tower, as their business requires, in |>erfect security. 

The tower is quadrangular, and has four or fivs 
windows on each side, represented 9t g g ; k h re- 
present doorways, the npper one leading into an 
external gallery i i, which, aa may be supposad* 
commsods an eitenflire and highly interesting view 
of London and its suburbs ; i is the stem of a long 
flag-staiT. The staircase, from the bottom to the 
top of the tower, is of iron, and of great itability ( 
it ia represented, of course, as disaected in Uie en- 
graving; the foot plates are of cast-iron, slightly 
fluted, to prevent slipping ; and there are square 
landing-places at eAch corner of the quadrangle, aa 
veil as seats for the convenience of the weary or 
laxf ascendants and descendants. There are two 
or three other towen similar in their arrangements, 
but circular, at no great distance from the one here 
described. Tliere is a round and lulVf shot tower 
near Newcaatla-Dpon-Tyne, from the balcony of 
which the spectator commands an intereating range 
of proBpcet, incladiog the river with ita vast asaem. 
blage of colliera and other craft. 

The various sizes of the sbot are disdnguisbed. by 
the maoufacturera, by the Not. 1 to 12 : the largas^ 
No. 1, are called swan shot ; the amallest, No. 12, 
dnit shot ; their diameter varying from one-thirtieth 
to one-fourth of an inch. The sbot, when removed 
ont of the tub, are dried by artificial beat, as they 
remain oousiderebly wet, by the water being held 
between the little spheres by capillary attraction ; to 
dry them, they are scattered over a large heated 
iron-plate, having a furnace beneath, on which they 
are well stirred about, and swept off as sooo as dry. 
After this operatioa, they present a dead white oiU 
very apjicarance ; they oootalo amongst them many 



C190 



MAGAZINE OF SCIKNCE. 



(thoufh but ft waaH proportion) of iiup a iftjU «iiotf 
and tbe perfect differ aomewhBt in sise ; (a tepante 
UiQWTsnekieft {ram one another coiutaftulOT tiwiioxt 
proMB. The dried thot ara« tiierelbfe, taken to the 
siilen, who have each the raanagenient of a eeriea 
of three or four sierea plaeed in a row, in a roctpre* 
eating iron fmae, which derives iti motion from a 
BlrrtTn-en^ne : tbe mavemcnt is effectexl by a hori- 
zontal revolving abaft [near the ceiling of the room), 
having at tbe extremity a short crauk, from which 
depends a rod that is made to riM op and down ; 
tfan vertical rod is attached at its luwvr extremity 
to a IcTcr of the common beU-cxank kind, wluch ii 
connected to tbe frame containing the sieves, snd, 
therefore, pmdures in the latter a reciprooatiBg 
horiKontal motion. Each gieve is also provided with 
a distinct frame embracing its circnmferenre, with a 
large joint on one side, which connects it to the 
general frame. A. quantity of the shot being thrown 
into the first sieve, that portion of them which is 
imaU enough passes through its meshes ; tbe net, 
that are too targe, are then dischargod into the next 
sieve, by funtmg over the first on its hinge joint, as 
a pernon would o|tea and tlu-ew back the tid of a 
box. The advantage of this amBgonaBt will be 
eviilmt, when it is considered that the rieves, being 
constantly in rapid motion, it would be no easy 
matter to throw the shot from one into the other, 
were they aeporate, without npilling ; wbereaa, by 
their connection, the shot cannot be discharged 
4>UiarwiBe than as intended. Tbe attendant on the 
dfting apparattii has, therefore, only to supply the 
Arst sievot and to discharge the contents from one 
to the other euooeaaiTely. Tbe prodBoe of the two 
first sieves is coUected into separate Una; and, as 
these contain many shut of imperfect ,^)r»ur, tbey 
are taken thence to another set of opemton, who 
separate the bad from the good, by a proeose aqMUy 
simple and eflectual. Thoic which bafe not paaed 
through the two first sievet of tbe series sit ooo- 
drmned as bad, and are remclted. 

A namber of shallow quadrangular trays, tiie 
figure of which may be defined by the boundary line 
of a plane, produced by the longitodinal section of 
tlie frustnun of a cone in the line of Its axis, made 
of bard wood, and perfectly smooth at the bottom. 
are suspended from the ceiling by oords attached to 
the two comen of the widest ends of the trays, 
their other, or narrowest ends, resting upon the 
edges of a row of ahot-bins. Thus arrsjoged, a 
boy, who mansges two of these trays, throws upon 
each at the widest end (that nearest to him) s small 
ncasure-fnU of shot ; he then takes hold of the 
trays, and« giving them a gentle vibratjog motion 
laterally, and st the same time raising the ends a 
liitle, to give them a slight inclination, the shot roll 
about, tending from side to tide, those that are per- 
fectly spherical making their way quickly off the 
boa ds into the bin at the extremity ; while those 
which are imperfect are detained by their eompara- 
tivdy sluggish movsowots; and, being thus sepa- 
rati^i froin the good, the trayi are pushed forward 
about a foot, and their contents emptied into oCbcr 
bins placed beyond thufie containing tbe good ahot 
as before mentioned. This oiieration is so efliBCtaal, 
that it is difficult to pick so imperfect ahoi out of 
those that come to market. Four or fire boys thus 
employed, with two trays to each, suffice for a ma- 
nufactory of tbe kind above described, which makes 
atwut fire tons per day. The smallest shot require 
tbe utmost care and gcotlet^t management of the 
incbnul plane; therefore the eldest or steadiest 




^OiA are selacled io openfee upon tbca* 
tad last port of tbe bnihi— , preriou 
bebig hegied for the maifcet, is to pobsh 
this poipose a osst-inm barrrl. holdtnf^a 
half a tell weight, is nearly filled with tl 
rotary movement eommanioated to it by the 
which causes all the littb spheres to r«b 
eaoh other, and gives them a black Inatre. mi 
diArioc from their previous argentine eofl>| 
It is remarked that a eorious effect is prodnoi 
the interior oftliecaitt-iroQ barrL-l by the frii 
the shot,— that of wearing it into a 
grooves ; so that a stranger would 
rel had been cast with sn internal 



JAPANNING TUNBR1DGE.W 

»T A -njNBaiPGS.WAJLB MA>-rrA< 

(Mtammei from pi^ 203^ on^ eoac-^ 

Ir is rather difficult to explain by words 
ing procesfl in l^tnbridgc-ware. as under 
circumstances and we^er, &c. the tii 
for drying,' fiic. varies very mncfa, and . 
trying it must nsethdr own judgment, a 
tlie nature of the siticle, and the polish _ 
ensore success. After the article is orname 
painted it must haTeaaqvarablodc of wood 
ing to its size, and from 4 to 6 inches 1< 
slightly on the bottom, to serve as a ban 
future process. It must then recti 
eight coats of spirit nmlih, this 
two days ; let it remain the foU 
vsniish room, that it nay srt gradnanj 
remove it to on airy place ; the more cum 
providing neither daoBp nor stisi can get 
better : let it rcmsift ktb ebout a fortn^ 
wish your work to stand wdl. When 
the varnish will ctack aU ovrj in v 
crocks. 

The next pmcea k teehnicolly 
dmtm — to do This piofUc r«ttrself with i 
finely grated cbaft, peffccQy free from g 
rubber made of thf^^tmUkA flat five or 
round a piece of very eCtf pisteboard, a 
of clean water ; ibip iqi flie key.hole 
or bees* -wax. and iscbig tin article by 
screws, or any way eonvaident, soak the i 
water, then, wbtk wet, cover it with t 
chalk dry , and witii tt r^ the article too 
and aftcrwsrdfl creeawsys, till the cradcs are 
moved, and the aurfiioe b perfectly flat and 
continually di]i;4nf yoar mbber in the wati 
taking freah dry dialk, but keeping yotu^ 
wet, and your hsilh also, te prevent thi 
printing — wipe olT oecadonilly with the 
your band to obesm tbe progress 
rubbing through. Be osn^ not to food 
your hands dry, as the rubbing softens the^ 
when smooth and even all over stand by 
a week — it will then be ready for polish 
is done in the same way as the rubbing 
dry chalk and water, only using a 
ruhWr, instead of the stuff one, and less 
thv finishing or smoothing is done with t 
the hand wet, without any mbber at al| 
the rt>qiiircd |>olish or brightness is obtaisn 
tukes but very little time, as It is suppoi 
perfectly Ant, smooth, and even, from the 
down. Jitid the polishing is only to ^ivj 




MAGAZINE OF SCIENCE. 



M* 



by a deticnte aod very tligfat 

lUb, no« thoroaghjy bard and «T«a. 

tiil the utat dty, tbeu unstop the key- 

off the block. aL-npe any of the nn* 

wbero tks cbiiik uid water may 

1. Line tbe iosde with aUk, latiii, 

or pftpoTf accordiaf to the^ naCttie at 

Tbeu oil aQ over tbe polished parta 

of (Unael* aoaked Id Florence oil ; and 

■ad fiaiah off with a very suft cotton 

d cosunon dour ; dry, and if wefl 

•IswetUks plaie gUas. This ia 

faaaft artidnii wUch can be much 

parpOM«: and every pervon 

■D ialorcatod, and makei a trial, will 

a practical knowledge of the peooaas, 

to fiaisb the articles according to their 

kys minding the lon^^r the time allowed 

> uwkiin, tbe more darnhle the work 

Inlaid Cuicy wood. Mosaic Tun- 

^ftniahed in tbe aame way ; but plain 

F^ocb pulished, which ia 

-Your'i, &c. 

usao. 



of nebulous ipoU are to be aeen on 

[el heaven, which have every appear- 

' Infters of stars, but are too duitant 

by tbe most excellent teloacoj 

appear to be mitter in the 
of rarefiurtioQ, giviug uo indication 
1 gteUar uture. These are in every 
from a wBgiaa film hardly to 
with trleicopea of the higbcat powers, 
acem to have actually arrived at a aoUd 
Tlua nchulona matter auat» in vast abun- 
fpac£. No fewer than 2000 nebulv and 
atam were obaervad by Sir William 
vrboae places hare been computed from 
Ltiou, redueed to a common epoch, and 
ito a catalngoe in order of right aacension 
r, Miia CaroUae Herwhel, a lady ao 
astronomical knowlodge and discovery, 
bnsdred nebols hne already been 
in the loutheru faemijq>here ; of theae 
douda are the most ra nut rk able, 
of thiB matter, scattered over 
fuch a Tariety of forma, is involved, 
, obacnrity. That it is a seU-lununous, 
material lubstance, in a highly di- 
atAte, but gradually subsiding by 
ritalion of iti particles into stirs and 
la, it the hypotheaia most genendly 
indeed, this is the hypothesis of La 
regard to tbe origiti of the solar system, 
eonniTed to be formed by tbe Boccesave 
of a oebula, whose primeval rotation 
untaincd in the rotation and revolution of 
and alt the bodies of the solar system in 
direction. But the only way that any real 
on thifl mysterious subject can be ob- 
by tbe drtermination of tbe form, place, 
state of eax'h individual nebula; and a 
of thcae with future observations wiU 
iona to oomc the changes tluit may now 
theat sBpposed rudiments ot htture 
ttab viewv Sir John Herscbel began 
182& the arduous and piona ta^k of 



revising his illnstrions fsdier'a ob«rrvationfl, which 
he finished a abort time before be »atlrd for tho 
Cape of Oood Hope, in order to dtsclooe the myste. 
riiia of the Boutfaero hemisphere ; indeed, our firma- 
ment seems to be exhaualed till farther, improve- 
menta in the tdeaoope dull enable ostronoment to 
penetrate deeper Into space. In a truly splendid 
paper read befbre the Royal Society on the 21 Rt of 
November, 1833, he gives the places of 2500 nebula 
and dosters of stars. Of these 500 arc new, — the 
rest he mentions witti peculiar plessore aa bavhig 
been most oocurately determined by hla father. 
Tbis work is tbe more extraordinary, as, from bad 
weather, fogs. twiBght, and moonUgbt, these shadowy 
appearanoea are not visible, on an average, above 
thirty nights in the year. 

The nebulv have great variety of fbrms. Vast 
moltitndea are so faint aa to be with diAcnlty dia- 
cemed at all till they haTe been for some time in 
the ticid of the tetMcope, or are just about to quit 
it. Occaamnally they are so Tague diat the eye la 
conscioos of somrthiog, without being able to de5ae 
what it ia ; but tbe tmchangeableness of its positioB 
prwrea that it ia a real object. Many present a 
large ill-defined surface, in which it ia difficult to 
s«y where the centre of the greatest brightness Ia. 
Some cling to stars like wisps of clond ; others ex- 
hibit the wonderM appearance of an enormona flat 
ring seen very obliquely, witli a lenticular vacancy 
in the centre. A very remarkable instance of an 
annular nebula is to be seen exactly half-way be- 
tween ^ and y Lyne. It is clhptical in the ratio of 
4 to 5, is shaqily defined, the Internal opening oc- 
capying about half the diametier. TIiU opening ia 
not entirely dark, but filled up with a faint hazy 
light, aptly compared by Sir John Herschel to fine 
l^uce stretched over a hoop. There is a very ro- 
markablo nebnla in Orion, and there la sooie rrasca 
to believe that a new star has appeared in it recently. 
Two nebnlc ore described aa most amazing objects : 
— One like a dumb-bell or huur-glaaii of bright 
matter, Burrounded by a thin hazy atmosiibere, so 
as to give the whole an oral fiinu, or the appear- 
ance of an oblate spheroid. This phenomenon 
bean no resemblance to any known object. Tbe 
other consists of a bright round nucleus, surrounded. 
at a distance by a ncbnloni ring split through half 
its circomferencc, and having the split portiona se- 
parated at an angle of ib° ^ch to the plane of the 
other. This nebula bears a strong aimilitude to tlie 
milky way, and suggested to Sir Jubn Uerschel ilia 
idea of a " brother system bearing a real pbjsical 
resemblance and strong analogy of structure to our 
own." It appears that doable nebnlc are not un. 
frequent, exhibiting all tbe varietiea of distance, 
position, and relative brightness with their counter. 
parts the double stars. The rarity of single nebulK 
as large, faint, and aa little condensed In the centre 
as these, makes it extremely improbable that two 
Burb bodies should be accidentally so near as to 
touch, and often in part to overlap each other aa 
these do. It is much more likely that they consti- 
tute systems ; and if ao, it will form an interesting 
snbject of future inquiry to discover whether they 
posseaa orbitusl motiou. 

SteLUr nebnlsE form another class. These have a 
round or oval shape, increasing in density towards 
the centre. Sometimes the matter is so rapidly 
condensed as to give the whole the appearance of a 
star with a blur, or Uke a candle ahuiiug through 
hem. In some instances the central matter is so 
highly and aaddanljr condensed, so vivid and sharply 



U9 



MAGAZINE OF SCIENCE. 



* 



ilefioed. that the nebala might be t&kn far a bright 
ttsr Kurroanded by a thin atmocphrrr. Sach are 
seboloaa stars. The xcxtiacal light, or ImtttcnUr* 
■haped atmoaphere uf the mn, which maj be leea 
dteading bejood Che orbits of Mercury and Venna 
■00& after mniet In the mootbi of April and May, 
ii nppoMd to be a condeiuatioQ of the etherul 
medium by hu attractire force, and aeeina to place 
OUT sun among the dan of liellar nebnlK. The 
atelUr nebula: and nebulous ktui awnme all degreeit 
of altiptidt7. Not anfrequently they are long and 
narrow^ like a spindle •shaped ray, with a bright 
nndeiu in the centre. The last claas mentioned bjr 
Sir John Uerachel are the planetary nebul«. Theae 
bodiea haie exactly the appearanoe of plaoeta, with 
•eosibly round or oval dlacs, sometimes sharply ter- 
minated, at other times hazy and ill defined. Their 
mrftoe, which is blue or bluish-white, is equable or 
■Ughtly mottled, and their light occasiofialljr rirala 
that of the planets In riridnesa. They are generally 
attended hj minute stars, which giro the idea of 
aooompanpng satellites. These ncbols are of enor- 
mous dimensions. One uf them, near i> Aquarii, 
hae a aensible diameter of about 20", and another 
pretenta a diameter of 12". Sir John Heracbel haa 
compnted that, if these objects be as Air from as aa 
the stars, their real magnitude, on the loweat esti- 
mation, must be such as would fill the orbit of 
Uraniu. He concludes that, if they be aolid bodies 
of a Bolar natnre, their intrinsic splendour must be 
greatly infiDrior to that of the sua, because a circular 
portioo of the con'a disc, subtending an angle of 
30", would gire a Ught eqnal to that of a hundred 
foD moons ; whOe. on the contrary, the objects in 
question are hardly, if at all, visible to the naked 
eye. From the uniformity of the discs of the pUne- 
tary nebulie, and their want of apparent oondenaa-' 
tion, he presames that they may be hollow shaUs, 
only emitting light from their surfaces. 

The existence of every degree of elltpticity in the 
nebulae — from long lenticular rays to the exact cir- 
colar form I — and of evrry tibade of cenCntl oooden- 
aation — from the slightest increase of density to 
apparently a aolid nncleus, — may be accounted for 
by suppo^ng the general constitution of theae nebula 
to be that of oblate spheroidal masses of eiery 
degree of flatness, from the ffphere to the disc, and 
of erery variety in their density and elUpdcity 
towarda the centre. It would be erroneoua, how- 
ever, to imagine that the forms of these systems are 
maintained by forces identical with those already 
deacribed, wluch determine the form of a fluid mass 
In rotation ; becanie, if the nebulK be only cluiitera 
of aeparate atars, as la the greater number of cases 
tkere la every reason to believe them to be, no prea- 
WQ can be propagated through theiu. Conse* 
quently, since no general rotation of such a system 
aa one mass can be supposed, it may be oonocived 
to be a quiescent form, comprising within its limits 
an indefinite multitude of stars, each of which may 
be moving in an orbit about the i-oinmoo centre of 
the whole, in virtue of a law of iuLernjd gravitation 
reaolting from the compound gravitation of all ita 
parts. Sir John Herschel has proved that the eiist- 
ence of such a system is not inconsistent with the 
law of gravitation under certain conditions. 

The distribution of the nebulm over the beaveni 
is even mure irregular thui that of the stars. In 
some places they are so crowded together aa scarcely 
to allow one to pass throagh the field of the teles* 
cope before another appears, while in other parts 
houn elapse without a single nebula oocoiiring. 




Tbey are in general only to be seen wid 
best tdescopes, and are most abundant* 
wboae general directioa ia not hr from 
circles Q^ and 12b, and which crusaes the i 
nearly at nght angles. Where that xone 
ooDBtellatioaa Virgo, Coma Berenices, an 
Bear, they are to be found in mnltitadea 

Such is a bnef aoeount of the 
tained in Sir John Herachel'a paper, 
soblimity of views and patient ioveati, 
boen anrpaased. To him and Sir Willijm)! 
we owe almost all that is known of sider| 
nomy i and in the inimitable works of tH 
gifted father and ion, the reader will fiodil 
ject treated of in a style altogether worthy 
of them. 



misceujvnies. 

^ponfoMow ComhutHtm. — Mr. ManhJ 
connected with the Royal Anenalr raoS 
covered that it is an invariable rale with n 
has remained for a considerable time anal 
when reduced to small grains, or to an W 
powder, to become red-hot, and to ignite i 
with which it may come in contact. Thl| 
rieoced by scraping some eorroded 
gun, which ignited the paper oomi 
burnt a hole in his pocket. The knowlei 
fact may be nsefu In acconatlnc for q 
fires, the origin of which haa never ' 

Gilding tff Meiait by BiKtro-C h e micat 
M. de la Rive has ancoeeded tn gilding 
means of this poweiftil Mtton. Hli m 
follows : — He poors a solution of cUori' 
(obtained by dissolving gold in a mixta: 
and muriatic acid,) as neutral as poeiible 
dilute, into a cylindrical bag made of 
then plunges the bag into a glaaa vend 
very slightly arsitulated water. The 
gilded is immersed in the solution of 
communicates by means of metallic 
pldte of line, which is placed in the 
water. Tlte process may be varied, if t1 
pleases, by placing the acidulated water 
the bag, and the sotution of gold with 
to be gilded on the glaas vessel. In the 
abont a minute, the mrtal may be with 
wiped with a piece of linen ; when rub 
with the clnfh It will he found to be slig 
After two or three similar immersions 
will be sufficiently thirk to enable the 
terminate the proceas. — Athenmtm, [I 
the silver plates used in Mr. Grove's 
batteries are always now done in the abo 
Silvering of articles of various kinds 
easy. M. de Rive is nut entitled to the 
OS it is a neceasary conacqucncc of Mr 
discovery. — Ed.] 

TMe Ckangtabh Rote.—T$k9 
blown red rote, and having thrown a lit 
finely pounded into a chaffing-dish with 
pose the rose to the vapour. By thia 
rose will become whitish ; but if it be 
immeraed some time in water, it will 
former color. 



L(in»oii:~Frtiitotl tiy D. Psakcu. <. WtiUt Hon* Lana, Mil* Kwt— rvbtlibad b]r W. BamAiH. It. Y* 



^^^^&=: 




THE 



MAGAZINE OF SCIENCE, 



5lni» rtljool of am. 



^2] 



KKW EDITIOH. 



[ijrf. 



^*9^ 




WAGSTAFF'S WIRE COVERING MACHINE. 







flppffimtrnpr 



TRACING AND PROFILE INSTRUMENTR. 



u. — no. XX, 



PRINTING INK. 

Inriof the difTerent preicriptiont given by 

Rton, PapilloD, Lewii, thoftc in NLcboU 

du Mctvn. AikinB* Dictionaries, in R«eii' 

■ad in the French Printer's Manual, 

»j», in his work on the ' ' Prcfwration of 

tKe EncjclopKdia BriUnnica is the onl/ 

b knowledge, which hu given a redp« by 

btiog ink might be made, that could be 

h it would be of inferior quality, aa 

pd by the editor ; for it Hperifies neither 

■ of the materials, nor tbeir dne pro. 

Hie fine black ink mode by Mr. Savu^. 

bnu Of. been proouunced by some of 

falters to be unriTallcd ; and hu procured 

lar^e medal from the Society for the 

cat of ArU. 

doiU — Mr. S. says, that the linseed oil. 
If boilad, unless set 6re to, cannot be 
It proper state for forming printing ink ; 
'flame may be most readily extinguished 
n of a pnitty tight cover to the top 
which should never be more than 
The French prefer nut oil to linseed ; 
latter be old. it is fully as good, and 
, in this country at least. 

ia an important article in the 
of good ink ; as by mt-Uifig it in the 
ingredient is safficiently boiled and 
two combine, andfonn a compound ap- 
to a ttttural balsam, hke that of Canada, 
one of the best Tarnishes that can be 
ting ink. 

r— Tiys is a moat important ingredient 

I Ink. which is not even mentioned in 

rectpes prior to that in the Encyclo]iirdia 

For want of soap, ink accumulates 

ice of the types, so as completely to clog 

jftar oompariuiTely few impressions hare 

it U will not wash off without alkaline 

skinsover very soon in the pot. Yellow 

■ b the best for black inks ; for thoae of 

Bflfr.fl* shades, white curd soap is piefcr* 

O moch aoap is apt to render the impres- 

lllar, ud to prevent the ink from drying 

Hie proper proportion has been hit, when 

nki clean, nithoul clogging the iurface of 

ip black, — ^Tb« Tegrtable lamp black, sold 

takes by far the most Yamish, and 

ir making the best ink. 

y black is too heavy to be nsrd ilone u a 

or printing ink : but it may be added with 

by gntidiiig a httle of it upon a mnllcr 

lamp black, for certain parposes ; for in- 

an engrmring on wood u required to be 

» ss to produce the best pocsiUe effect, 

F^ alone, or with fin pq-uil weight of Pnifl< 

added in small proiwction, takes ofT the 

: of certxin lamp-bl.ick inks. Mr. Savnge 

Kts a little Indian red to be ground in with 

a and Prosfian blue, to give a rith tone to 

ink. 

ens ^cffprn', OS sold by Mr. Allen, Plough 

>M.h<ird Street, miied, by a stone and a 

lioe proportion uf soap and pigment, 

< ' ' laporaneoiu ink. which the printer 

loy very advantageously when he wishes to 

job \fi a peculiarly neat manner. Canada 

JOB not aoiwcr qaitc so will. 



After the smoke begins to riM from the boiling 
oil, a bit of burning paper stuck in the cleft end of a 
long stick, should be applied to the lorfaoe, to set it 
on Are, sa soon as the vapour will bum ; and the 
flame should be allowed to continue (the pot being 
meanwhile removed from over the fire, or the tire 
taken from under the pot.) till a sample of the vsr- 
nish, cooled upon a paltet-knife, draws out Into 
strings of about half an inch long between the fin- 
gers. To six quarts of linseed oil thus treated, six 
pounds of roiin should be grsdually added, as soon 
as tlio froth of the ebullition has subsided. When- 
ever the ro^in is diaM>Ued, oue pound nnd three 
qnarters of dry brown soap, of tlie best quality, cut 
into slices, is to be introduced cautiously, fur its 
water of combination causrs a violent intumrsocnce. 
Both the rosin and soup sboold be well stirred with 
the spatula. The pot Is to be now art upon the lire, 
in order to complete (be combloation of all the con- 
stituents. 

Put next of well ground Indigo and Prussian bine, 
each 2| ounces, into an enrtheo pan, sufficiently 
Urge to hold all the ink, along with 4 pounds of the 
best mineral lamp black, and 3^ pooods of good 
vegetable lamp bUck ; then add Clie warm varniah 
by slow d<;grccs, cart'i'ully stirring, to produce a per- 
fect incorporation uf all the iugrcdifnls. This mix- 
ture is next to be subjected to a m'dl, or slab and 
muller, till it be le>'igated into a smooth unlfona 
pute. a 

One pound of a superfine printing ink may be 
made by the following rrcipe of Mr. Savage : — Bal- 
sam of captvi, 9 02. ; lamp bluck, 3 ox. ; indiguaad 
Prussian blue, togethiT, p. teq. li oi. ; Indian red, 
I o2. ; turprutinc (jrllotv) soap, dry, 3 oz. This 
luiiturc is to be ground uiion a slab, with a muller, 
to an inipalpaUe Ktnoothaet*. The pigments used 
for coloretl printing inks are, carmine, lakes. Ver- 
million, red lead, Indisn red, Venetian red. chrome 
yellow, chrouie red or omtgr, burnt trrraili SiemtOf 
gall-stone. Roman oclirr, vcllow ochre, vrrdigriat 
blues and yellowy mixM fur greens, indlgu, Prussian 
blur, Antwerp bUe, lusLie, umber, sepia, browna 
mixed witJt Yeoetiou red, Ate. 



FUNDAMENTAL 



PRINCIPLB OP WHEEL- 
UOttK. 



iw the construction of whwl-work considerable 
'attention ought to be paid to the shdpe of the n- 
riuiut parts, us much of the etlicicncj and jrrrmaoency 
of the work dcjiendi on this. 

The teeth should bo so formed, as that, 

1st. TliC teeth of one wheel shoutil press In a 
directioQ perpendicular to the radius of the other 
wheel ; or. in other words, the prirs»ure should be 
tangential to the wheel which is driven. 

2Dd. Aa many teeth as possible should be In con- 
tact at the same time, In order to dbtribute tlia 
pressure amoog»t ibcm, nnd 'ln'ri-by tudituiniiib the 
prr-twrr upon ra^jh tooth. This arrsngrmtrnt will 
dimini;^h the wear, and thr chances of fracture. 

3rd. During the entire iti.-iioo of one tooth upon 
another, the dircctiua of the preiiuie should be th% 
wme, in order tlint, scLing with the same leverage, 
the eETert may Iv: unifurw. 

4th. The surfticea of the teeth In working should 
not rub one upon another, and should suffer no jolt 
citlicr at the commencement or termination of their 
mutual contact. 



156 



MAGAZINE OF SCIENCE. 



Various fonns hafe been euKg«Rted for the teeth, 
with R view to the nccompHshmcnt of (tome or all 
of chese advancaget; bat that which eeemi best 
calculated to attain the deiircd endi is the fol- 
lowing . 

Suppose that PHI, Kg. 1, la the circuinferenoe 
of thr. wheel on which it is propoved to raise teeth, 
and let H be oae of the poinu from which the ^de 

Fiff. 1. 




of ■ tooth is to Bpring. Suppose a string is attached 
to the circumference of the wheel as at 1, and applied 
to the circumftrrence I F, aiid terniiuHtcd at H, 
carrying a pencil at its ej:tremity. Let the string, 
being constantly stretched, be rolled off. so that 
that part of it, F C, whirh has b«cn disengaged 
from the circumference of the wheel, shall be 
in a straight line, tuucbing the circumference at 
F, and in this way let the pencil describe the curve 
H C ^. Let (I H be the breadth of the tooth at 
the circumference of the wheel ; and attnching a 
airing in like manner to the other side of the wheel, 
and rolUu|r it on in the oppusiCe direction, so that 
its extremity bearing the pencil sluill be at d, let a 
aimibr curve be described. These two curves wilt 
include a space which will represent the form of a 
tooth which will accomplish all the purposes, and 
possess all the advnntages we have mentioned. 

The teeth of the pinion, of course, are to be 
formed in the same manner. 

It is a remarkable property of these curveSi that 
a line P E which touches both circles will pass 
through the point of contact of the teeth, and not 
only of one pair of teeth, bat of every pair which 
ore in contact : and this line will be perpendicular 
to the direction of the surfaces of the teeth at the 
point of their mutual coutat*t. Thus tlie pressure 
of the pinion on the wheel is exerted tongentially to 
both, and therefore acta always with tbe some 
leverage, and to the greatest advantage. 

Farther, daring the whole period of the contact 
of any two teeth, the pressure acts in the same 
direction, nod with the same forct*, and therdore 
when it is onifonn, it necessarily produces an 
uniform effect. 

During the motion, the surface of one tooth does 
not rub or tcrape aguin«t the Burrice of the other, 
but the one roll* upon the other, Ihercby removing 
Bcarly all the clTcctA of friction, and diminishing 
•onsldernhly the wear of iha mariiincry, anil the 
waste uf the power. 



Several teeth are in contact atthe same 
all working with equal power, so that the - 
equally distributed among them, and the d 
fracture are greatly diminished. 

Thus this form of tooth has all the 
which can be desired. 

In regolating the number of teeth in 
and the pinion which works it, it should b 
trircd that the tame teeth should be cngogj 
dom as possible, in order to avoid ini 
wear. For example, let as suppose tlutt 
ber of teeth in a wheel were exactly ten 
namber of leaves in the pinion ; each 
pinion wouJd engage every tenth tooth of 
and would work inevitably on the same 
every revolution of the wheel. If it « 
that all the tt^th and leaves could be 
with mattiematical precision, and }ferfect d 
lute similitude, and that no accidental M 
owing to any want of unifonnity in the ma 
which they are formed, could exist, this M 
matter of no consequence, and the wear «j 
be even and equable. But as these pa 
never can exist, the inevitable ioeqaolities I 
as well to the nature of the material o 
wheels are ooostructed, as to the forms 
even from the most perfect meobudml 
Aust be compensated by making tfaa 
leaves work, so that each leaf shall 
engage with all the other teeth of the whi 
it engages a second time with any one of A 

This li sooompUihed by making the in 
teeth and the number of lea\-es primr to efti 
that is, that no integi^r divides both exactl] 
manner in whidi this is commonly done, is 
the number of teeth such, that it is jnst 
than a number which is exactly divisi! 
number of leaves. This is what mill- 
making a hunting eog. Thus, suppose 
are ten leaves, and that the diameter of 
is about six times tliat of the pinion. If 
the exact ratio, there woold be just sixty 
after each revolution uf the wheel the 
end leaves would be continually engaged, 
taking every atxth tooth. But if the 
tlie wheel be made somewhat greater than 
that of the pinion, so as to admit sixty 
then, after six revolutions of the pinion 
leaf will be engaged with the tooth 
before that in wliich it had worked at tf 
mencement, and after six more revolutioa 
be engaged with the tooth before that, or tb 
tooth from that at which the motion com 
Thus, it is evident, that the wheel mod 
G I times, and the pinion G x G I , or 366 til 
the same teeth will be again engaged. 
meanSf the innpialilies of wear urising 
equalities of form and material will col 
each other. 

The teeth of the wheel, instead of wortt 
leaves of a pinion, are made to act upon 
wheel called a Itxnicm, as represented at 



fig. 2. 





MAGAZINE OF SCIENCE. 



157 



'fyfindrioal tcFth or ban of the Untem are 
ti tmiUi ■ or tjttnHteB. However, nntwith- 
If thft nriou5 forms of wheel-work, the 
lie* whtcli wr have ftlreaily explained will 
detennine ihe relation between the power 



I are denominaCed spitr, crmm, or bevfj 
according to the position or direction of tbe 
ir llitf teeth be perpciidlruUr to tJie axil of 
rel, nnd in the direction of radii, as in the 
Fig. 2, it ia called a ipmr-trhfri. If the teeA 
illel to the axiR of the whrcl, and therefore 
Aealw to iti plane, it is called a rrotrn-wkefl. 
[Hkr-wheels, or a fpar-wheel and pinion which 
n one another, are always Id the same plaact 
TV their axb parallel. But when a spur and 
vfaecl are in connexion, ihctr planes and 
•e ftt right angles. By tin* means, tlierefore, 
ry motion may be transferred from a boriMn- 
a Tertieal plaae, or rice ver*^. 
a the teeth arc obliqur to the plane or axis 
wheel, it i« catlnt a bcvdlcd-whceL Two 
t of this kind are repreacntcd In Fit/. 3. 





caae. (lie surfaces on which the teeth are 

parts (if the forfaces of two cones. The 

which these wheel act, and the principles 

formation dcpenda, may be ooncetTcd 

uing two cooea to be applied side to side. 

fttcea have sufficient friction, and one of 

upon its axis by a mechanical force, 

!l Ibc iither to revolve ; and if tliL- bases 

be equal, each will retulve in the same 

^ut if the diameter of the bfute of one be 

any ituntber of times the diameter of the 

ulbcr, then the leader cuue will revolve 

ia unc revolution of the greater. 



kt that what we have observed of the 

e ponr«. will be equally true ol nuj ports of 

. ...■i',iiy Jistaat frum their common vertex, 

'. would be true of wheeis, the edges of 

I .iitK nl the conical surfaces. 

lite fdrtiQH of ihe conical surfuces be insuf. 

nt to transmit the force, the surfaces may t>c 

in f^. ^ 



and if the cnnical surfaces be iocompleta, they will 
become berrtlfd'tfihftlM. 

It will be easily perceived that the a.«e of bevelled - 
wheels is to proiluce a rotatory motion round one 
axis by means of a rotatory motion round another 
which is oblique to it; and, provided that the two 
axes are in the same plane, this may always be ac- 
compUahed by two berelled-wbeeU. K lystem of 
wheels td this kind is repreacnted in 
Fig. 6. 





PREPARING SKELETONS. 

Sm much of the fleshy parts should be removed 
from boiica intruded for preparntion sb possible with 
the scalpel, but itb not required that ibey should 
be separated from each other, more Lluui is uecessary 
for placing thtm in a vessel for the purpose of roa- 
c«ratioa. The bones are to be entirely covered 
with water, which should be changed every dny for 
about a week, or as long as it becomes discolored 
with blood ; after which, allow them to remain in 
water without changing till putrefaction has tho- 
roughly destroyed all the remaining flesh ; this will 
require from three to six months, according to the 
season of the year or tentpersture of the atmoe- 
phere. ^^'e here speak of Great Britain, but in 
wanner cUmatea putrefaction will take place more 
rapidly. In tropical climnLes. fourteen days will 
be sufficient to disengage the flesh completely from 
the bones. 

The Inrge cylindrical bones of the thighs and arms 
should have holes bored <ia their extremities of the 
sixe of a ifoose quill, to give the water access to 
their cavities, and a free exit to the medullary sub- 
Btance. 

Aj tlie water will gradually diminish in quantity 
from evaporation, more should be added from timo 
to time, so thnt none of the bones, or any part of 
Uiem* may remain uncovered, as by exiwsurc to the 
atmosphere they would become of a dirty color. 
and have a disagreeable appearance. To bo free 
from such stains is considered a great beauty in 
skeletons. 

In towns the macerating vessels should always be 
closely covered, as from neglecting this, tlio water 
is apt to get mixed with particles of soot, and other 
impurities, which hive a strung tendency to blacken 
the honea. ^'ben the putrefsction has destroyed 
tlie ligaments, the bones are then tit for cleaiting, 
which iH done by scraping olf the flesh, ligameuis, 
and periosteum. When this is effected, the bones 
shuuid be again laid in clean water for a few dnys, 
and well washed. They ought then to Iw placed iu 
lime water, or a soluliun of pearl ash, for ■ wfck, 
when they may he token out to dry, oftrr having 
soaked them five or six boars in pure watrr, to 
remove the solution of pearl-ash, which would act 
upon their surface when exposed to the atmutpbcrc. 

In drying buuee they should nut be ex posed to 
the rajs of the sun, or to a Are, ai too groat a 



108 



MAGAZINE OF 8CTENCE. 



degne of heat bringt the mnaining medulhry oil 
into the oompaet aabctanee of the boaet, and etvea 
them a diaagreeable otly tmuparency. TLU ia the 
great objection to the proceat of boiling bonea, for 
the purpose of making akeletona, as the beat applied 
in that ws^ has the same effect, unless they are 
boiled in a solution of penrl-nsh. which some are of 
opinioa is one of the most effectual methods of 
whitening them, by its cffrctualty destroying the oil. 
Bat then; can be but Uttle doubt that bleaching is, 
of all methods, the moat effectual where it can be 
done to its greatest advantage, namely, in a pore 
air. and more especially on a sea-shore. 

it U much more difficult to clean the Bones of 
animttff that have died in good condition, thsn 
those that are lean and reduced by disease. 

Nahtrai 5'i(efr/(ni«.— Natarml skelrtona are made 
without aeparmting the bones from each other, in 
which caw all the animal ligaments are allowed to 
remain entire. This plan is generally adopted with 
young and smal] animals, because the ligomenCs, 
when dry, being dlTected of their nitiiral flenhility, 
occasion an inconvenience, as the difTerent extents 
and varieties of motion cannot be shown in the dif. 
fercnt articulations. 

In making these, we are first to remove from the 
boneSi tfaeskin, musclea, tendons, and viscerB, and, 
In short, every thing except the comiecting liga- 
nenta and cartilages, which ought to be cnrefully 
preferred. This is done without any regular order 
of dissection ; neither in this part of the process 
need any attention be paid to making the bones 
cleaa, Tbe braiu maybemuoved thmugh an open- 
ing in the large fontanel, if tbe subject is «L!r7 
7onBg, if not, a perforation may be made for that 
purpose. Some separate the head from the spine, 
to Chat the brain may be the more euily removed by 
the uccipiLal hole. The nkeleton is put in wntf r. and 
allawctl to reuiAia for several dsyt ; it is then tiiken 
ont, and more thoroughly dcaoed by a knife, for- 
ceps, end scissors, and replaced in frrsh water. This 
Is repeated from day to day, constantly changing the 
water, the object being to preaerve the ligaments 
fresh and tninsfiamit. It is of great conse(|ueiice 
to work hard, by daily Kfaping nod scrabhing, until 
the bones are deprived of ttf ir blood and oleaginous 
matter, and become white and clean ; thvn remove 
tliem into clean lime water, or solution of pearl-a*h, 
for two or three dayi, to take off any greasiaeas, 
and give a more beaotiful white. When they have 
tain long eooogh. wash them with clean water ; they 
are then placed in a position, by the assistance of a 
fnma, or piece of wood aad wire, exposing them to 
a ovrmt of air. Whan perfectly dry, Ihry may 
roodw a coating of copal or mastic varnish. 

It nait be kept in view, that if tbe prepsralion is 
■Bowod to remain too long in the state of inocera* 
Hon, the UgamottCa tbemsclTea will be destroyed by 
putrefactioQ, and tbe iotcotioo of procuriug a aa- 
turml akeleloa ddlaated. 

Aa CTcalWat and simple way of procuring natural 
■ItelatOiia of mice, small birds, and fish, is to put 
than fario a boi of the proper sixe, in which holes 
ara bored oa all sides, and thro buried in an ant- 
ML Hie ants will enter numerously at these boles, 
aadaal sway all the fleshy parts, leaving only the 
fcoBaa mA eoaiieeling ligaments . they may be after - 
VMili MMHVted ha etaan water fur a day or two. to 
•ftraet the Uoody eolor, and tu dcaose tb«m fi'om 
any dirt they otay ban aoqwlred ; tbw widtanod by 
UoM and alum woiar, aad dried ia tnmm or wl ha r 
«iH, aa Buy ha asil manwkaL la 




tions, wasps may b« csnpAojad hi lUi aa 
are moct voradoiis amowbr and If a 
placed near ooc of their oeata, or b sa wftf i 
cask, where they resort to piraty* thj wfliM 
the disaection with mach greaM* Of 
eqaaily well as the ant». Wup* ha«a &■■ i 
to clean the skeleton of a 
three or four boors, wblla ansi «a«U nv>at< 
to effect it. 

When the animal ia of a brga aba^ ' 
are sometimea vnahle to anstain tha **Wi 
bones, in which case, aa iro« wii^ iiai 
thickness, is passed through Iha oantra af 1 
bone, which roost paaa oat anmkw i y , m m I 
the head to the cervical vartrina. U la i 
form of two forks, the ona fer tha 
anterior, and the other for the 
this purpose two piooea of tran-wvo an 
length of the skeleton ; they ira 
leaving a fork at each extremity, i 
fixed to the board on whioh tka ak^Eian hi 
placed. One of theae ihoaU onlar tAa 
eacompasf the bade hooa» btiwuen iW 
bonea on Mcfa riuwlder, the dkar tvo 
between the bonea of the pelTta, 

It not unusually happens thaS piaaMaf 1 
leton detach one from another, hi wMd 
holes are bored In the ends cf tho baac^ 
separated, and are re>iinitcd by SMaaa of i 
wires. 

Arhjicial ^hfffnai TTkaJatraa af 
mala of a middling and la^ 
in the manner described for 
tbis case, the bones, cofvrcd by Che 
lucTBcd in watrr. and aUoaad 
changing it, until Che soft parte ba(la ta i 
when the aoioial matter is caafly 
repeating the aueeration two or 
all be completely abstracted. TW 
sary fur tbe first usceratian «fl 4t^ 
state of tbe aLmosphrrc, being alvaiya 
ill summer than in winter. 

After the fleshy matier baa 
from the bouea, they ahoold ha 
uf a house, or other < 
are rendered aoite whitei aad ftan 

The fst in booaa 
Axed oils. In the boaca of whalae 1| 
like oil. In the loag booai of 
other Urge quadrupeds. It b acas 
the marrow. TAlurn, therelBn^ Ihia b 
cofudderable quantity, the pnioaa May be 
celerated by ilrilling hoka 
ioftrument, in the opposite »da af Ifce 
injecting by means of e syringe, a 
pearl-ash. the pot.«ah ooBibUag «iib (he < 
nutter, furming a kind of sosy^ which hrfav i 
la water, ii eaafly maoradi CUadda^l 
also employed for the aeaa paipoaa. 

Tlie relative pnmortioa af aartky 
matter variea aooordiBg to dw m^mn ti te I 
and the pnrpuaca Hl ia tailendad 
bones of quadruped* aad bMa mattM a 
grealrr propftrtioa of earthy 
reptiles and Aahea, aad I 
Here it may be rwifhed. that the aehr <f 
variM ia ditfercat enlwtle la aaa 
U infoaehaa to a dark |«tto«hfc 





demonaCrated la 

Wh«a the boaea ara acribel aiai 
aaoncctcd by aaaa of ava aad ten 



MAGAZINE OF SCIENCE. 



159 



most difficult [tart of the operation, as it re- 
ccosidenble skill to rtiasMmble the boDcs. lo 
toft lliej may be plni-ed in their natonJ order and 
MitfOB. The opentioa it began st one of tiie ex- 
CBUtie*. by making bole* in the apophftit, or 
faad b&U of the bone. This in effected bj meaiui 
' m wimble or a lathe, or with a gimlet, ^thoo^h 
fei mstnunent has hardlj mffideDt power for per- 
mt&nf ao hard a fubvtanee as bone. The honea 
|fe thai attached to each other in their natural 
HP^ mth nealfd iron-wire, or bnAi wire, by means 
^^^Hlbrationi which have been made. The endi 
^^^^^P fthould be twisted, and not too Armly, 
f^HnJent to allow a little play between the arti- 
Ution ; this mode ii to be pursued HII the whole 
raw put together. They are then ready for 
Mine on a board, and are kept erect by mcani of 
|^<r two perpendicalar bars of iron, commensurate 
H^weigbt of the Bkeleton. In the larger epeciea 
^Hdi. one support ia neceassry; it ia passed 
|M^ Uie breast bone, and attached under the 
Inc The position of this oiipport must be raried 
cording to the attitude in which the skeletoD is to 



In tkeletoDfl of the hontc, the ox, the hippopo- 
hDua, the rhinoceros, the camel, and the elephant, 
B links of wire which wa hare above described, 
B inioffident to unite their bones ; for these, two 
M p*%9 are used with a head at one end, and a 
at the other. Each screw is provided with 
'•ad each pair of. screws must have a narrow 
'«f Iron bored at each end to pass the screw 
SappORing the buues of the leg and thigh, 
inrr qandmpi^d, are to be united, a hole is 
' '' ripopbyiis, about two inches from 
• I the same baring been done with 
Uc; dw* t.tMi:ii-boneji, they are brought together, 
A ooe of (he 8<-rewft pissed into one of the boles 
tbe plates which we hare mentioned, and then 
irvM^ the perf}ration» In the bone, and la.«tly into 
k Other pUite ; thry are tightenrd togrthrr by 
MM of the nut. The screws Ghould h« nearly au 
elk toskger than the thickness uf the bones. The 
of the bones are thufl united and Ktip- 
by the two pUt«« which are kept toKethcr 
' the srrrwa. Prorision must he made for the play 
the bones, by lenving a tudicient difttance in 
1^1^ the holes, through which the pegs are 

^^p liorM, and other Urge animals, require a 
^^m bar to support them. A bar ia also passed 
^B^ the rertebre of the neck, spine, and tnil, 
jHCe ribi are attached by means of wires, or flat 
Mk9 of piste iron. 

In these larger snimaLi, the heads are for the 
ioal partaawQ through, for the purpose of studying 

tstnicture of the internal cavity and partitioos. 
se are kept together by means of a hinge, lO 
bS dicj can be opened and shut at pleasure. 



k 



CRYSTALLIZ.\T10N OF ALUM. 

IVi prindple of this pleasing operation has been 
Uctfy ooofiocd to the fabrieatioQ of flower baskets 
br chimney ornaments, snd the enchasement with 
a artifidal crystal of busts, Ice, but the more ez- 
Muive application of aluminous crystallisation may 
t intfodaoed, as promising a somewhat higher order 
f gnttteatioai more particularly to the lovcra of 
Utaay aad other bnncbes of DStur^ history. 



Dissolve 19 ounces of pare alum in a quart of soft 
ipring water, (observing the same proportion for a 
greater or less quantity), by boiling it gently in a 
close tinned veasd, over a moderate lire, keeping it 
stirred with a wooden spatula until the solution is 
complete. When the liquor is a/ffi/>i/cotd,suKpend 
the subject to be cryitillized by means of a small 
thread or twine, from a lath or small stick laid ho- 
risontally across the aperture of a deep glazen earthen 
jar, as being best adapted for the purpose, into 
which the solution must be poured. The respective 
articles should remain in the solution 24 hours, when 
they are taken out they arc to be carefully suspended 
in the shade until perfectly dry. The whole process 
of cryitallization is best conducted in a cool situa- 
tion. When the subjects to be crystallised are put 
into the solution while it is quite cold, the crystals 
arc apt to be formed too large ; on the other hand, 
should it be too hot, the crystals will be small in 
proportion. Experiments couvloced us that the 
best temperature is about 95^ of Fahrenheit's ther- 
mometer. 

Among the vegetable specimens, are the common 
moss-rose of the gardens ; the protuberance or ^r 
.foand on the wild rose, rosa eanina, occasioned by 
an insect deponiting its ova thereon, this should be 
plucked with its foot-stolk and free of its leaves ^ 
small bunches of hops ; ears of corn, especially 
miUet.seed, and the bearded wheat; berries of the 
holly ; fruit of the sloe-buih ; the hyacinth ; pink ; 
furze •blossoms ; ranunculus ; garden daisy ; and a 
great variety of others : in fnd, there are few sub- 
jects in the vegetable world that are not eligible to 
this mode of preservation. 

In the animal kingdom, the lizard ; Urge spider ; 
grasshopper ; all the beetle kind ; the nests of small 
birds, with their eggs ; form beautiful specimens 
when neatly secured on portions of the brAnches of 
the tree, Sec. on which they arc accustomed to rooxt. 
A considerable degree of attention is requisite to 
prevent too great a deposit of the alum on some of 
the above-mentioned subjects, by which their beauty 
would he obscured, they ought therefore to he fre- 
quently inspected while cryBtalUaatiun is going on, 
and removed as eoon as it can be ascertained they 
have acquired a sufficient coating. Various articles 
of turnery, 8cc intended as chimney ornaments, la 
almost every diversity of form, if first carefully co- 
vered over with common cotton wound round them, 
may be submitted to crystaltiiation with the same 
beantiful result. 

The crystallized subjects may be tingeil with al- 
most auy variety of color, by boiling in the alum a 
solution of a little indigo, Brazil wood, logwood, 
French Oerricn, or other vegetable and mlncnd dyes. 
A little care and ingenuity will enable the operator to 
confine his tints to the crystal surrounding the flower 
blossoms, and other particular parts of plants 
which be may wish to preserve. 

Amongthe cryptogomic tribe, the class of lichens, 
especially the cup-moss, are most eligible subjects, 
nor are many specimens of fungi leas adapCed ', the 
two latter tribes of vegetables have morsover the 
advantage of iiermanentiy retaining th«ir own co- 
lors, without any aid whatever from art. A tliin 
coating of the crystallizing matter only should he 
allowed to obtain on most individuals of cryplogn- 
mia, which is adequate to their preservation, and 
eaaential to the beauty of the specimens. 



1G0 



MAGAZINE OF SCIENCE. 



» 



I 
I 



COLLECTING BRITISH INSECTS. 

Woodt, Ifetifffu, ami l^anfii. — By far the ^at£at 
portion of iiuecto are found in these ntuaUoni. la 
woodi, tbe Entomologist must beat the brancbea of 
the trees into bis folding net, and most select for 
thi« purpose the open paths, skirts, &c. The trunka 
or tnvfl, gates, and timber vhich is cot down, should 
be careAilly exMntned, as a great many Lepidop- 
terona and Coleopterous in&ccts arc found in theae 
fitoations, and In no other. In bed^es and lanes, 
many of the most valuiible and beantifol insects are 
found, 04 also in nettles and other plants which j^ow 
under them ; these should be well beat, bat more 
especially when the white thorn bloaaoma la the 
months of May and June. Hedges where the roada 
are dusty are very seldom productive, 

Hest/u and Common*. — Many inaects are peculiu- 
to theae situations from the plants which grow on 
them, as well as from the dung of eattle by wlucb 
many of them ore fretitieuttfd ; in the Utter of which 
many thonsands of insects may be found in a itngle 
day, in the months of April and May. Theae are 
principally of thr order Colroptera. 

Simd Pit*. — These Are fjivurable for the propa- 
gation ot Capri* tunariuM, SotnsuM monorertw, Iasum 
tmteiroBtrii, and other rare iotccta. Minute speciea 
■re found abundantly at the roots of graas. 

Meadoteg, Mar»Me», and Pondt. — In meadows, 
when the Ranunculi, or buUer-cups, are in bIo<siOm, 
many Muaca and Dip(erou> inf<ecta generally abound. 
The flag-rushes are the habitaliou of Cmdm, Do- 
tucnet and others. Drills in manhea ahoakl be 
eiamined, aa many species of insects arc found on 
long grasa. The UrvK of various Lepiiloptrra. and 
Neoroptera, are coufitied to theae Btaations. more 
eapecially if hedges and tree* are near the spot, 
ponds are rirh in mirro*<'opic insects. Tbe« are 
obtained by means of tliclnutlint; uet, which should 
be made of pretty thick cotton cloth, but sufficiently 
thin to allow the water t» escape. The mad which 
is brought up froo) the bottom of poods and ditches 
should be eiamined, and what amall insects are 
found may b« put in a smsll phial filled with water, 
which will not only clean them, but keep them alive ; 
and in many inataocea tlie naturalist will be sur. 
prtsed upon the examinatioo of theae, the nioat 
vonderfbl prodoctiooa of nature. 

itfMff, Dfeo^ 7Ve«t, Aoob tfGnut, 4*^.— Many 
ISMOti will be found in moss and under it ; the roots 
•ml wood of decsyed trnts afford nourishment and 
& habttBtion to a number of inaecta ; many of the 
UrvB of Lepidopi0rm penetrate the tranks of trees 
bk all dlrectioni ; noat of the Cerambyoea feed on 
wood, aa wvU aa some apedia of Chi ' riirf a, S/afe- 
rid^t !». In aeeking for tlheM, It U oaceaaary to 
aae the digger. It hi sometimes reqnialte to dig six 
or aevon inchea into the wood before they are found. 
Bamlt tff PoiuU, ad Jtoofi ^ Grass.— TboM are 
a never failing aouroo of collecting, which may be 
foliowfv! at all aeaaOQa of the year, and, in graeml, 
wiih gr^at lucosaa; those banks are to be preferred 
which h»yr th« morning or noon. day sun. 

BmtM iff Hirfn, Smdy S^a^Mort, ^e,— Thrse 
ritasAlooi •ffonl a grait variety of 0>/eo;»/rr«, (Vus- 
loTM, &c. The dMd caroasca of animals thrown on 
(he ahors abonld be eaamlnod, as thcv arc the re- 
eks tad food of SiM69d0, Sl^'ktlmdm, Aic. 
■mI Jime are the bast sMtOtta for COllocHng 




onoilitBte 



of several inaeeta. It la not 
people to hang dead moles oo fuaaro ; 
the entomolugiat aliuulil place hia aritf 
the boughs on which they arc husf • M 
Coleoptera generally inhabit these. 

PkMffi and Floitert. —These sse ik* 00 
of insecta, and many curious 
on them. 

It is a mtstakea ides that 
found in sununor, as Ihay ar« to b* astwIA. 
in a living or pupa state, at sU sessoas* OtM 
beueath the bsrk of trees, s 
extremely likely places to ftnd jp aocli JK 
even then, the entomologist is 
core Boms of the rsre spcdco, tiMB te 
theae are rsnging in search of food, «ai Ift statfiM 
hidden from view. 

At this season, if the westhsr io ■ahl. As r^fm 
of Lffidopttra will be found at th* tvota of ti«% 
more especially those of the elm, ook« ItaBK. ftb V 
beneath the underwood, dose to Iho tov^aarftt^ 
frequently at the depth of fOBO locfcoi IbIv %m 
ground. 

In the montha of Jtuio, Jolfi 
woods are the beat plaoH to tm kih 9h 
Most of the bntterflics are taksn fen tfcsss 
flying sbout in the day .Urns only 
found at break of day, or at twilight fah tlis 
The following method of tthteg l o fhs Is 
out by Hawortfa. la spceking «f lbs Oak 
(BomSpx Qwreea;. ** It is s 
with the London Anreliana,** «y« bs. 
breed a female, of this and some 
species, to tske her. whUst yet s 
vicinity of wood*, where, if the moMtt li 
able, she never fsiLs to attnet s 
males, whose only businesa aeems lo ks as 
sant. rapifl, and undulating AigihA, ia MMdi I 
unimpregniucd femalea ; ods of vhU ia •• 
perceived, than they beeome so maA 
ihflir fair and chaste relation, as ehsi 
all kind of fear for their own peraoaal 
at other times, is effectually aecncwd hy 
evolutions of their strong and rapid wi 
less. Indeed, have 1 beh«U thM m tk 
u to climb np and dowm tbo iUsi of ■ ei^ 
contained the dear object of tbdr w^ 
exactly the same horryiog msoDsr i 
which have lost Lhcmsalvea, dimb aii 
glaaactf of a window.'* 



«a^ DrMI Bgntt, sbooU be co«* 
for theas are the oateml hahitsti 



TbfAs 

Sia. — At our works wv ere In tkl InM 
considcrmble quantities of cklorUa ef bm 
purpuac of bleaching our oottoa fDo4k 
purpoae we dissolve, (say two or ttswi 
weight) of the anlt In water, ml let 
affair settle : the clrar Ili|«id wbkb ■as* 
the solntioa m ese. Ons day lael aeasi 
aeddeat. happened to stir sp one of Iks 
this solation Is kept ; and was s eiim aM 
great arototion ef agss t I hsflMwA. vsl a 
collected « ooealderable quantity. 1 
got oxy^re, bceriy pure. I wi 
thet itM« fMonlly scinoe lodged foct, lk«l « 
ilfrnmiin— weCer ; bat, 1 new tehHn bee* 
tbet frm e«yyM w«a «*alTOdL If N Is 
accMdary dlsoofer^-ffy «h«ec I trnf tmi 
aotioeof the 



r*»J»*j 



419 D. rsAMna,CWMlfHwwLaM. MU»Bsd.-rsaiHeMlby W. leiatao^ It. r si ii a m— > 




THE 



IIgazine of science, 

B ^nh ^tbool of Strfse* 



So, LXXIIL] 



BSCOND mOITION. 



[Price I^ 




INFLUENCE OF POINTS IN ELECTRICITY. 



ELECTRICITY. 

tSaumtJ.fronfAg* 115) 

I liffv in forver |Mp«r» upon thia snbject had 

»4nqiktties of witDctsiag the efl*ecC of. and ex- 

iaiiif tbe lawa tlial appcrUia to the eleciric fiatd 

rABieri>a» of its pb«ce«. It prrbnpt will be now 

ii»i>«' In coDkidcr wtuiC is tbu fluid ; for nume- 

na wiii aaCnrally bare been uskcd upon 

•nJ tlic ftodcnC will deairetr) know not 

■■: acts, hat what it is. To aatisfj hta 

. !y i« tm|Hi(i«ible, so little do we know 

„ I. But that i« the Mf*e aUn with heat 

Mifbt. ^^'« know thein but from their cO'ecta — 

mD calculate thiir ))Owera, but their origin 

YM.. II. — NO. XXI. 



exrapn oa. All thirefora that can bo nr^d la 
auppositioii, supported it may be by suffideDl ar- 
Kunent and eiperimtut to go far to change that 
theory into proof. 

The first great qneition that aris<4 u — la the 
electrical fluid material ? Or, in other worda, la it 
a 8*ibntanc<} ? We are inclined to think that it it. 
and the followini^ remarks and iUuatntioDs aeem to 
confirm the opinion. 

It ia stihjeri to romprevsion and dilafition, aa we 
tee in the positivr and negative aidta of a machine 
or in a charged phial. 

Ita attractive and repulsive power ia not |M>fiitive 
but relatire to the particular atate of oi^cumulatioii 
in which the apparatus exists. It compressea the 
air in iCi paatAge thfotigh it u ia aeen iu the spark 







OT k UlK WVfCf froB 

of tbreJ 
ucextn 
Ab 1^ wA ofn Wiws. tW psp nty bt ti 

to iuf li h i the dhcMical 
a^ m^K af Acol lead. sitDplj foU 
. WWbcvtt tlw paste hu lusl iu gn 
r, il » rcWj fert>«B*rcr iato « terie*' 
a^a, to W fertbcr dilubnl ud wufed, w| 
ihK dear Mfcrpbotphftte of lime m»j be ma, 
■ lypboo &OM tlM (lepcMit of gfjmim. Mora^ 
MWt tkcB be nixed with Uu preelpiutv, ~ 




MAGAZINE OF SCfENCE. 



168 



to^liirh, the supcmatiint Uqaor i.i agnin In 
ofl*, The skilful operator ttiupluj« Uiu 
from nri« ciuk to wuih the depoiit in 
U Oierrby nves fuel in evaporation. 

-'*•■' '■ r> being put into a leadeii, or 

, in, of proper dinienaioos, are 
■ '. steady euallition, till the cal- 
t breoinea coDsidrrable ; ailir the 
been allowed to cool, the cle^r liqnor is 
ff, the sediment removed, and thrown on 
rhe enporation of the clear Uqoor is to 
bU U acqairea the cousisU-ucp of honey. 
milghnil. it should amount to 'M poun(U. 
oiiiM weight of charcoal in fine powder, 
ut 9 pornidH, are then to be incorporotrd 
I the miiture \i to be rvnpornted to dry- 
■t-iron pot. A |?ood deal of snlptiurous 
ea^grd along with the steam at first. 
rfactinn nf the salpburic acid upon the 
■nil afterwarda Kome sulphuretted hydro, 
the miitnre has become perfectly dry, 
f the redness of tlic bottom of the pot, 
allowed to cool, and packed ti^hl into 
jara fitted with close coven*, till it is to 
to distillation. For this purpose, 
rta of thf best quality, and free from 
must be taken, and c%enly lufed over 
a compost of fire-cl'iy and horsc- 
the coeting is dry and feound, the 
two-thirds filled wiHi the powder, 
upon proper supports in the Uboratory 
ace, baring its fire pl'icnl not imme- 
eath the retort, but toonr sidi. after the 
rcTcrberatory ; whf rchy the flume may 
ml]r round the retort, and the fuel may be 

1 it is wanted, wiihout adtnitling cold air 
|er its cracking. 

beak of the retort properly inclined, the 
r a bent copper tube U tn he tightly luted, 

other end ia plunged not more than one 
r an inch beneath the surface of water 

in a small copper or tin trough placed 
rloK to the side of the furnace, or in a 
thcd bottle. It is of advnutage to let the 
aomewhnt warm, In order to prevent tlic 
1 of the phosphorus in the copper tube, 
conseqncnt obstmction of the passage. 
be htak of the retort appear to get filled 
1 phosphorus, a bent rod of iron may be 
Dd passed up the copper tube, without 

P^mI from the water. The heat of the 
■I be roost tlowly raifted at first, but 
Itobly mafaitauied in a state of bright 
After 3 or 4 hoars of steady firing, 
and aulphuroua acid gauea are evolved 
ble abundance, provided the tnateriala 
been well dried in the iron pot ; then 
Xed hydn^n maken its appearance, and 
nphorctlcd hydrogen, which Ust should 
during tlie whole of the distillation, 
ing fihoutd be regulated by the oneapc of 
jknhle gas, which ought to be at the rale 

2 bobblri per second. If the discharge 
be interrupted, it Is to be ascribed either 
D^ierature being too low, or to the retort 
Bracked ; and if upon raising the heat 
ly no hubbies appear, it is a proof that 
'»tus has become drfrrtivc, and that it is 
to continuR the op*'rBtion. In fiict, the 
rty in dintijting phnsphorns lies in the 
lent of the fire, which roust l»e incefsnntly 
and kd by the successive introduction of 



fuel, coni^ting of coke with a mixtiure of dry wood 
and croal. 

We may infer that the process opprnaches its 
conclusion by the incre-asing tlDwne» with which 
gaa i» diMingngcd under a (wwerful heat; and when 
it ceases to come over, wc may ceoae firing, taking 
care to prevent rttlux of water into the retort, from 
condeBsatiun of it^ gaseona eontents, by admitting 
air into it through a rcoarred (kus tube, or through 
the lute of the copper adopter. 

The Qsual period of the operation upon tltc great 
scale ii from 24 to 30 hours. Il» theory is very 
obviooa. The charcoal at an rUratcd tf^uiperature 
disoxygeoates the phoepboric acid with the produc- 
tion of carbonic acid gas at firxt, and aftorwnrds 
carbonic oxide gaa, along with sulphuretted, carbu- 
rettrd, and phowphu retted hydragcu, from the re- 
action of the water prcMot in the charcoal upon the 
other ingredients. 

The pbosphoms foils down in drop.s, like melled 
wax, and concretes at the bottom of the water in 
the receiver. It requires to be purified by squeezing 
in a chamois leather bag, while immersed nnder the 
surface of warm water, contained in an earthen pan. 
Each bag must be firmly lied into a ball form, of 
the size of the fint, and compressetL, under the 
water heated to 13^^ by a pair of flat wooden 
]»inoers, like thosic with whirh oranges are squeened. 

The purified phoaplioriis is moulded for *ate into 
little cylinders, by melting it at the bottom of a 
deep jar filled with water, then plunging the widet 
end of a slightly tnperiug but straight glass tube 
into tlie water, sucking thi» up to the tcp of the 
glass, so as to warm it, next immersing the end in 
the liquid phosphorus, and sucking it up to any 
desired height. 

The tube being now shut at bottom by Ibe apnU- 
cation of the point uf the left index, may be taken 
from (he mouth and transferred into a pan of cold 
water to congeal the phosphorus; which then will 
commonly foU out of itself, if the tube be nicely 
tapered, or ntay at aay rate br poshed out with a 
dtitT wire. Were the glass tube not duly warmed 
before Ftuckingup the phosphorus, this would be apt 
to congeal at the aides, before the midiUe be filled, 
and thus forn hollow cylinders, very troublesome 
and even dangerous to the m-ikers of phoftphoric 
match-bottlei. The monlde<l sticks of phoephonis 
arc finally to he cut with scissors under water tu the 
requisite lengths, and put up in |iltiab of u proper 
size ; which should be filled up with water, closed 
with ground stoppers, and kept in a dork place. 
For carringe to a distance, each phial should be 
wrapped in paper, and fitted into a tin-plate case. 



PURIFICATION OF WATER ON SEA 
VOYAGES, 

When long kept in wooden casks, water undergoe* 

a kind nf putrefaction, contracts a disagreeable sn.. 
phureous smell, and becomes tmdrinkable. The 
influence of the external air is by no meous neceS' 
sary to this change, for it happens in close vessels 
c»cfi more readily tbim when freely exposed to the 
atmospherinil oxygen. The origin of this impurity 
lies in the aiitnal and vegetable juices, which the 
water ongiimlly contxined in the Aource frnni which 
it was drai^n, or from the cask, or InBCcij", fee. 
' Thr«e ntntlirs easily occasion, with a suffirient 



164 



MAGAZINE OF SCIENCE. 



winntb, lermentatioii in the stagnitnt whSxt, and 
thereby cause the evolutioD of ofTcnKive g&£-es. It 
would appenr timt the gypmin of hard water* U 
dfcompoBcd. and ^vea up itn solphar, wb:ch Dggn,- 
Tites the dinogrecuble odour ; fur seleiutic wnterii 
arc more apt to take thia patrid taint, than those 
which contain merely carbonate of Ume. 

Aj the corrapted water has become nnfit for nae 
merely in consequence of the admlxtarc of tbete 
furuign matters, for water in itself u not liaMc to 
corniption, ao it may be piiri5c-d again by their 
N>parBtion. This puri&ciUion may be accompUsIied 
most easily by passing the water through charcoal 
powder, or through the powder of rightly calcined 
bone-black. The carbon takes away not only the 
finely diffused corrupt particles, but also the gaseous 
impurities. By adding to the water a very little 
sulphuric acid, about 30 drops to 4 pounds, Lowitx 
■ays that two-lhirJv of Iho charcoal may be saved. 
Undoubtedly the sulphuric add acta here, as in 
nther limilar irajes, by the coagulation and separa- 
tion of the albuminous matters, combining with 
them, and rendering them more a]it to be fjeiscd by 
the charcoal. A more elTectual agent for the 
purification of foul water is to be found in alum. A 
dram of pounded alum should be dissolved with 
•gitatkm in a gallon of water, and then left to 
operate quietly for 24 honra. A scdimrnt rolls to 
the bottom, while the WRtcr btH:ome)« clear abore, 
ttlld uiay be fWDfcd o(F. The alum comhines bera 
with tbw substances dissolved in the water, as it 
does with the stuifs in the dyeing copper. In order 
to decompose any alum which may remain in solu- 
tion, the equivalent quantity of crystals of carbonate 
of soda may be added to it. 

The red aolphate of iron acts in the tame way aa 
alum. A few drops of its solution are sufficient to 
purge a pound of foul water. The foreign matteni 
dissolved in the water, which occasion putrefactioo^ 
become insoluble, in consequence of oxidixement. 
like vegetable extractive, oou are prt^plt&teU. On 
this account, also, fbul water may be purified, by 
driving atmospheric air through it with bellows, ur 
by agitating it in contact with fresh air, so that oil 
iu particles are exposed to oxygen. Thus we can 
explain the influence of streams and winds, in 
counteracting the corruption of water expOMd to 
them. Chlorine acts still more energeticaUy than 
the air in pnrifying water. A little aqueous chlorine 
added to foul water, or the transmifsion of a little 
gaseous chlorine through tt, cleanses it immediately. 

Water-caskd ought to be charred inside, whereby 
uo fermentable stuff will be extracted from the 
wood. British ships, however are now commonly 
provided with iron tanks for holdinij their water in 
*«>« Toyages, 



UXtJSTHATlONS OF BOTANY- 
(JUtnmwl from page 133.^ 

ClsM XrV. — OiotNAMiA. Two orders. 




A totally different guide to claosiftcatioa b 
opened. The number of the stamens is not 
to be n^arded, rcfrrence moat also be made to 
compantive length. Quite different also li 
character of the plant. Their 6ijwers are m 
small, and crowdrd together io whorls — at Id 
the firrt order, which contains the Mints, Lam 
Hyasop, Thyme, llorcbound, Dead Nettie, indl 
numerous others, of a siaular kind — all ana 
carminative, and harmless. 

Not 80 with the planU of the second or 
some of Uiem aru highly poisonous, for exal 
the Pox .glove. Thia flower shows that the it 
not without st least one beautiful plant. Nor i 
alone, for the Snap-dragon, the Toad Fhix 
beautiful Gloxinias, the Bignonias or Trv 
Flowers, the Acanthus, (hollowed by architeci 
and the Musk plant, a species of Mlmnlua, 
not be forgotten — tin pUnta of thia claaa 
square hollow Ftems, lipped ooroUc, mostly fivn 
calywa, in the first order, opporite leavi 
generally bear pink, purple, or white 
flowera. 



1 



Claaa XV.— Tctkaotkahia. Two orte 




4 



Stamvoi four loaf and foor thMf. 



3fwri*i)i tnv liiitj( nml ODt ihort* 



A class even more natural and unifom 
anc« than the latft. The plants are 
known by the cmciform or crou.shaped | 
their four petals. They ore for the mott 
herlM, with alternate leaves and scentleM 
mostly of a yellow, pink, or white col 
blue. Familiar examples of Tetradyni 
in the Vall-fiowcr, the Stock, and the 
which art' almost the only fragraot plants 
to the class. Other examples may be fot 
Cabbage, the Turnip, the Horse Radish, I 
Creos, the Candy Tuft, the Virginian 9 
well-known Bpring salads, Mnstard and i 
the delicate eiUble, the Sea Kale. 

CiaM XVI.— MoHODSLFHiA, Seven 



/ 



Stamnu uoiird tofcUiar law ooa but 

A smalt class, rendered highly inter 
count of the favorite plants U contaii 
Tamarind tree is among them, and one of 
beautiful description. Its leaves are pinael| 
of a fine green, the calyx and corolla ] 
the pods hairy and browu, the whole tree ni 
ei^e, and widely spreading out its numerous bra 
The Stork'S'bill, (commonly called Geraj 
conaisting of some hundred tpeeics. the F 
Sowers, than which the vegetable kingdom do 
produi-e more elegant plants. The Tiger flo 
no lea elegant. Abu ! that it ahould be . 



MAGAZINE OF SCIENCE. 



ie5 



ukI djins within ft few houra. 

iTe Jkmily of the Mallows is auuthcr 

lus, $0 iTC Uu> UibiBciu. the Lnvatcra, 

ly-hock. We must not forget Also cbtt 

itre«,aQd the Camrilm. among the i|)ccirj 

■re thoie ihrubi which |iroducc Uie black 

en te«f are of the cliu* Mouudelphisf aad 

Others belonging to It are wholesome in 

Bi. 

-TizDirinds nuj be ceailf gnwa in & 
hani; ool; neoeeury fint to nbe them in 

The Bcedji 08 fonnd in the pruerred 
Ot too old, will readily gcrminatu, and if 
1 brought into an apartmcDt will lire 
c summer, and not only be elepmt plants, 
la will bo ircn to close thrir petals every 
on/old them in the morning— illuatraCios 
mia nuDner the alecp of plants. 

KVII.-^DiACBtrHiA. Four orders. 






SfauDcw anitptl into two l>ujidl«a, 



l^.^.J^. ^ 



pbnta here placed, no lets than in lomeclaaflefl 
rnentianed, contain oatward marks by which 
•y he generally known, namely, their butter- 
|j^ flowen. and long pods of ser<l. There 
Wf great iiumoer of thia character, not merely 
Ited over the temperate and tropical regioDS, 
kerc either wild or cultivated. Very 
are tliin, delicate, climbing wcedn, as 
id the Vetch ; otheni are thii:kl;r flowering 
trees and shrub*, witiu'ss the Acacia, 
itUD, the Ebony tree, the Coroailla, the 
the Broon. Smaller plants are also 
wo aD patronise tlie Sweet Pea, tlie 
Kidney, the Scarlet, and the Broad Bean, 
rort, and the Milkvetch, The valuable 
pUnta — the Saintfoin, the Lucerne, and 
Oar iaUnds alone produce no lean than 
Tvpecies of thii clan*, while there have been 
into cultivation as many as a thousand. 

in.— POLTADKLPHIA. TwO Ordcf*. 



Class XIX.— SntOKNBBiA. Rre orders. 




)n •evtril tmtMlIva. 



V 3« 



igly smalt class of showy ond useful 

leaded m tlie hrst order by the (Ihociilate 

lose splendid green-house plants, the 

lelalrucas, commence (he second order, 

)wed hjr the genus Citrus — different 

which are so esteemed, as the Oranjge. 

ime. Citron, and Shaddock. The native 

shoos plants arr con5ncd to the genus Hy- 

or St. John')i-wort, a showy, yellow, in- 

,£unily uf ['lonta. 



n 



SUrhiu uaitrtl t:|ctbcr liy Iketr ftnUicn. 

This is a perfectly natural arrangement of plants, 
which are totally different in character from all 
others. Tlieir dowers, (such we should call them, 
if applied to other plants,) are in reality bancfaes of 
flowers oU upon one receptacle, thercfure called 
compound flowers. The Dulsj and the Oaodelion 
are well -remembered instances. The gardens owe 
much of their beauty, partictdarly in the autumn, 
to plants of this description. Were the splendid 
Dahlia, (pronounced Dal-io, not Da-lea,) the only 
plant, it would redeem the class from neglect ; 
but this is not all, an infinite multitude of plants, 
mostly well-known and some of them of sur- 
passing beauty, attract our attention before pasaing 
onward. Among them are the Lettuce, the 
Hawkweed, the Succory, the Burdock, and the 
Thistle, the .\rtichoke, the Cacalia, the LaTender 
Cotton, the Tansy, M'ormwood, Everhuting 
flowers of various kinds, the Colt's-fout-Gronndscl, 
the great family of the Aster or Stsrwort, 
Michaelmas Daisy, the Golden Rud, Cineraria, 
loula, the diifercnt Mirigulds, the Ziuuta, tha 
Chrysanthemum, Feverfew, Cluimoaiile, Yarrow, 
the Sunflower, the Rutlhcckia, the Coreopsis, and 
the Com Cockle. Almost all these plants are bitter, 
and none of them poisonous. 

The numerous genera are diitingoished from eacli 
otlier chiefly from the difl'erenccs observable in the 
receptacle, the r^lyx, or involucre, and the seed^ 
according as they may be bore, or crowned with ■ 
pappus. 

(Tb be continutd.) 



ASSAYING OP METALLIC ORES. 
(Rennud from jmfft 144, and concluded.) 

Cobalt Orta. — Free them as innrh as posKtblc 
from earthy matters by well washing, and from 
sulphur and arsenic by roasting. The ore thus 
prepared is to be mixed with three parts of black 
flux, aud a little decrepitated sea-salt : put the 
mixture in a lined crucible, cover it, and place it in 
a forge-fire, or in a hot furnace, for this ore is very 
difEcult of fusion. 

When well fiised, a mutaliic regulus will be found 
at the bottom, covered with a scoria of a deep blna 
color : as almost all cobalt ores cuutain bismuth, 
this is reduced by the same operation as the regulus 
of cobalt ; but as they are incapable of chemically 
uniliiig toi;cther, tliey arc always found distinct fiom 
each other in the crucible. The regulus of bisuiuth 
having a greater specific gravity, is always st tlie 
bottom, and may be separated by a blow with a 
hammer. 

In th* Humid Way. — MaKe a solution of the ore 
in nitrons acid, or squa-regia, and evaporate to 
drynesB ; the rrsiduum, treated with the acetous 
acid will yield to it the rohnltic part ; the anicoic 
should be first precipitated by the sddiUou of nater* 



MAGAZINE OF SCIENCE. 



Mfrcrtrial Ores. — Tbe calciform oitb of mcrcnry 
nrr eamily rt^uced without any atMition. A quintal 
of the ore u put into « retort, and a receiTer luted 
on, containing ■orne water ; the retort i« plocpd in 
a sand.bath, and a luffieieat degree of heat given 
it, to force over tbe mercury which u condtnixeU In 
the water of the recciTer. 

BuJyMurated Mercurial Ortt.^TUe lulpboreDas 
om are aaiayed by diatJllatiou in the manner above, 
only these ore« require an equal weight of clean iron- 
filings to be mijied with them, to disenga{;e the 
anlphur. while the heat volatilizca the mercury, and 
forcei it into the receiTcr. These ores whould 
likewiu be tried for cinnabar, to know whether it 
will answer the pnrpose of extracting it from them : 
for this a deterniinatr quontitr of the ore ii finely 
powdered and pat into a ^bm vessel, which is ex- 
posed to gentle beat at first, and gmdually increased 
till nothing more la sablirocd. Bjr the quantity thus 
■oqidred a judgment may be fonned whether the 
proceaa will answer. Somctimrs this cinnabar ii 
not of so lively a color aa that which U used in 
trade ; in this caie it may be refined by a second 
tublimation, and if it be still of too dark a color, it 
may be brightened by the addition of a quantity of 
mertmry, and mbliming it again. 

Humid Aj»ay qf Cinnabar. — The stony matrix 
■hoold be disaoUed in nitrous acid, and the 
cinnabar, being disengaged, aboold be boiled in 8 or 
10 timet its weight of aqua-rcgia, composed ot 3 
parts nitrous and 1 of mnriatic acid. The mercury 
may be precipitated in its running form by zinc. 

Siiwr Ore*.— Take the as»ay quantity of the ore 
finely powdered, and roast it well in a proper degree 
of heat, froqaently stirring it with an iron rod ; 
tbtn add to it about double the quantity of granuls- 
lead, put it Into a covered crucible, and place it 

a fbmaoe; raise the 6r« gently at ftrst, and 
intinue to increase it gradually, till the metal 
begini to work ; if it Mhould appear too thick, make 
ft thtnnrr by the addition of a little more lead ; if 
tbe nicUl sltould Ikjil too rapidly, the fire should be 
dimint^hrd. The surface wUl becovored by degrees 
with a moss of M-oria. at which time the metal 
should bo carefully »tirred with an iron hook heated, 
^■prclally towurds thr border, lest any of the ore 
sliDiiUI remain undissolved ; and if whst is adherent 
lo flir hook irhrn raised from tht crucible, melta 
quirk ly again, and the extremity of tbe hook, after 
tt U (crown cold, is covered with a thin, shining, 
smooth (Tust, the soorificotion is perfect ; but, on 
thr rnntrary, if while stirring it, any cnnsiderablo 
dammlnesi li perceived in the jtcoria, and when it 
ftdbcEroa lo Uw hook, though red hut, and appears 
Voeqaally tinged, and seems dusty or rough, with . 
grains tntenpersed here and there, the scorification 
is incomplete ; in consequence of which the fire 
should be increased a little, and what adheres to 
the houk should be grntlv beaten off, and retnmed 
with a Bmnll Ifldle into the crucible again. When 
■corification is perfect, the metal should be poured 
ioto a rone, previously rubbed with a little tallow, 
and when it becomes cold, tbe scoria may be separa- 
ted by a few strokes of a hammer. The button is 
IIm produce of the assay. 

Jly Ctpet/ation. — Take the assny (pinntityof ore, 
fMiland grind it with an equal portion of litharge, 
dHtd* it intti 2 nr 3 ports, and wrap each up in a 
vmall plsrs of psprr ; put a cupel preTiously 
under * muffle, with about 6 times the 
vt ksd u|M>!» it. When the lead beg;inB to 
inMh, MHtfully put ou« o1 the papers upon it. ond 



after this is absorbed, put on o second, and 
the whole quantity is introduced; then rail 
and as the scoria is formed, it will he t«| 
the cupel, and at last the silver will reou 
Thia will be the produce of the vsay, | 
lead oontaina a smaD portion of silver, wl 
be discnvered by putting an equal qunud 
same lead on another copel, and workii^ 
the same time ; if any silver be produced* 
deducted from the assay. This is called ih 

In the Humid ff ay.— Boil vitreous sil^ 
dilute nitrous add, nsing about 'Zb time:s | 
until the sulphur is quite exhausted. 1 
may be precipitated from the solution I 
add, or common salt ; 100 grains uf this | 
contain 75 of real silver ; H it contain a^ 
will remain undissolved. Fixed alkalies | 
the earthy matten. and the Prussisn fl 
show if any other metal be contained in th< 

To Aifojf tkt value of Stiver. — TM 
method of examining the purity of s3i 
mixing it with a quantity of lead proporl 
tbe supposed portion of alloy; by Mi 
mixture, and afterwards weighing tbe I 
button of silver, fliis is the same p 
refining silver by cupellation. 

It is supposed that the mass of sfl4 
examined, consists of 12 equal parts, eaUl 
weights ; so that if an ingot weighs aa oM 
of the parts nil) be l-12th of an oanoe.' 
if the mass of silver be pure, it is eoUed 
12 penny-weights; if it contain 1-121 
weight of alloy, it is called silver of I 
weights: if 2.'l2ths of its weight be 4 
called stiver nf 10 penny-wdghts, whick 
silver are called & penny -weights. It 
observed here, that assaycrs give the naa 
weight, to a weight equal to 24 real grah 
nnat not be confounded with their idea] 
Tbe assayers* grains are called fine gr^ 
ingot of fine silver, or silver of 12-peniq 
contains then, 288 fine grains ; if this ingc 
l-2RHth of alloy, it is said to be silver of ] 
weights and 23 grains ; if it cootaio A- 
alloy, it is said to be 1 1 penny -weights, . 
Sic. Now a certain real wei^t must oa 
represent the assay weights : for instance, 
represent 12 fine penny-weights ; this is i 
■ into a sufficient number of other smaUet 
which also represent fractions of fine penn 
and grains. Thus, 18 real grains reprcri 
pmny - wei(;hts : 3 real groina a^ rei g 
nenny-wei^'ht, or 24 grains; a real gn 
naif represents 12 fine grains; l-32nd i 
grain represents a quarter of a fine grain^ 
only l-7&2nd part of a mass of 12 pCDBj 

hauUe AMtay r^ Silver. — It is cosli 
make a double assay. The silver for 1 
should be taken from opposite sides of || 
snd tried on a touch-stone. Aaayets ko 
nearly the value of silver merely by the \a 
ingot, and still better by the test of the to« 
Tbe quantity of lead to be added is r^ 
the portbn of olloy. 

The cupel must be heated ird hot fne 
hour before any metal is put upon it, by 1 
moisture is expelled. When the cupel § 
white by heat, lead is put into it, and' 
increased till the lead become:! red hot 
and agitated by a motion of all its parts. 
circnlation. Then tbe silvei is to be p8 
cupel, and the fire coutinued liU the 



i 



MAGAZINE OF SCIENCE. 



167 



lead ; snil when tlie mass circulates well, 
be diminUhed by cloiiag more or 
ir of the usay fumac«. The heat »hoald 
1, that the metal oo \ti surface may 
res and ardcDt, while the capol U less 
HUDlcfl ihall riM to the roof of the 
nndalaboof shall be made in all direc- 
iCkat the middle of the metal shall appear 
Ith a small circle of litharge, which ia 
unbibed by the cupel. By ibiti (reatmeot 
alloy wiU entirety be absorbed by the 
sUrer become bright and shining, 
to lighten ; after which, if the 
m well performed, the silver will 
with raiiibuw colom, which quickly 
cross each other, and then the bottom 
and »oltd. 

lination of weight shows the quantity of 
lead contains a small portioa of silTcr. 
it with that used in the assay is tested 
product deducted from the assay weight, 
ia called the witness. 
Piatfd SdetaU. — Take a determinate 
the plated metal ; put it into an eartheo 
a sufficient quantity of the above men- 
it io a gentle heat. When the 
it mast be collected with common 
ibuit be tested with lead, and the 

ffding to the product of silver. 
rthM containing Gold.- — No. 1. — That 
most generally uaed is by amalgama- 
iropcr quantity \a taken and reduced to a 
ikbout 1-lOth of its weight of pure quick- 
and the whole triturated in an iron 
'The attraction subsiatiDg between the gol 
tier, quickly unites tbcni io the form of 
whiL-U ia pressed through chamoii 
(h« guld is easily separated from tUi 
by exposure to a proper degree of heat| 
iporate* the quicksiWer, and leaves the 
enpcratioa should be made with luted 

'the foctodation of all the operations by 
* is obtaiiwd from the rich mines of Peru. 
America. 

-Take a quantity of the gold. sand, and 
Ubot, quench it in water ; repeat this two 
les, and the color uf the sand will become 
Then mix it with twice its weight 
rerive tlie litharge into lead, by 
portion of charcoal -dust, nod ex- 
B proper degree of heat ; when the lead 
jq»araces the gold from the sand ; and 
«f the gold from the lead must he 

by cujKlLation. 
fieq^man assayed metallic ores oon- 
by mixing 2 parts of the ore, well 
washed, with U of litharge, and 3 of 
the whole with common salt, and 
ia a naith*! forge, in a covered crucible ; 
led the crucible, pnt a nail into it, and 
to do so, tlU tho iron was no longer 
lead was thus precipitatad which 
>ld, and was afterwards separated by 



separated from the aqua regia by pooring ether opoD 
it ; the ether takes op the gold, and by being bomt 
off leaves it in its metallic state. Tile solution may 
contain iron, copper, mauganese, calcareous earth, 
or argil ; if it be evaporated to drynevs, and re- 
siduum heated to redness (or half an hour, volatile 
alkali woU extract the copper; dephlogiaticated 
nitrous acid, the earths ; tite acetous acid, the 
mangaaese ; and the marine acid, the caU of iroD» 
the Bulphw floats on the ftist sulutioa, ^in which 
it should be separated by filtration. 



^f Guld mi-Ttd trith Martial 
OisBoWe the ore in twelve times its 
dilute nitrous acid, gradually added ; 
a proper degree of heat ; this lakes up 
le parts, and leaves ihe gold untouched* 
he inaolable matrix, from nluch it may be 
■ b/ squs regis. The gold may be again 



CHEMICAL TESTS. 

Tksts are substances which detect the presenoe of 
ulher substances in combinstion with any solvent, 
or known compound body. Their action depends 
on the affinity existing between the substance aidded, 
and any component part of the body under trial ; 
whereby a new compound body is formed, dtfTcnng 
catentitlly both from the test and the body acted on. 

7>tt for Aikalin, — If a few drops of tincture of 
turmeric are poured into any alkaline solution (of 
potass, soda, or ammonia,) the beaadful yellow 
co^or of the tincture will be converted to a deep 
brown. As a more convenient test, a piece of psper, 
linen, or cotton stained by tincture of turmeric (and 
kept dry for experiment) may be dipped in a solution 
of either soda, potass, or ammonia ; on withdrawing 
the test pafier, the part immersed will be brown 
instead of yellow. 

Litmvi Paper a Tetf Jbr Acid*, — ^ITiia psper Is 
prnpared in the same way as the turmeric paper, only 
that in this case, tincture of litmus is nsed. It is 
an excellent test for the presence of all the acids 
rxct^pt the pruHsic. By these, its 6ne bine color ia 
.nivariably converted to deep red. 

TVf/ for Carbonic Acid. — Dissolve some car- 
bonate of potass in water, and dip a piece of litmus 
pap T in thr solution ; it will assume a dark blue 
colo*. If it be DOW withdrawn and held over the 
vessel, at the same time that sulphuric acid is 
dropped into it ; the wetted part of the paper will 
be converted from b/ue to red. This change arises 
from the disengagement of the carbonic, by the 
sulphuric acid, which seising upon the potass, 
drives the carbonic acid off with efferrescence. 

Proof that Potamum is the Ba$t qf PotoMw^ and 
Sodium of Soda,~-Dip a half sheet of tumeric 
paper in a basin of distilled water, and shake off 
the auperflnous drops : spread it on a shallow plate 
and drop on it a large globule of potassium, or 
sodium. Either of theee will immediately oom- 
mcDce a rapid motion in all directions od the paper, 
staining it of a dark brown color, in lines, as It 
moves along. Here the potassium ur sodiom baring 
a great affinity for oxygen, combines with it 
wherever it is to be found in a weaker state of 
affinity for any other substance than fur itself. In 
this case, the dtstillerl water is decomposed, and its 
oxygen sot free : the oxygen combining with the 
metnl. The brown color of tlie staina on the paper, 
is owing to the action of a new formed subst-mce 
on the vegetable coloring matter uf the turmeric. 
This new subatance is the oxide of potassium, or 
sodium ; or as they are usually called, potass or 
soda. Therefore potass or soda being sXkalies have 
the characteristic effieet of alkalies on this coloring 
matter. 



)68 



MAGAZINE OF SCIENCE. 



7Vr/ ^ loAittf. — DuMohre k drachm of ftarch 
in half a pint of wat«r ; add about five graloB of 
iodine in another half pint : on mixing the soIti- 
tionn, a beautiful blue color will perwdf tlie mixture, 
and in a short times a precipitate of the same color 
will tales place ; which is iodine of starcli. The 
blue color if indicatiTe of Mtnration ; but if the 
ftarch prevails, it vrill hare a violet hue, and if the 
iodtne ii in excetf, the color will incline to black. 
If in any liquid containing iodine be combined vitb 
nnother Bubstance (besides water) it muat be first 
set free, by adding to the liquid a few dropR of 
lolpharic acid ; and then pooring in the solutioa of 
starch. In this way a hali' millionth part of iodine 
may be discoTered in any liquid. 

Suiphvric Acid and Baryfet, TeaU Jar each 
other. — Make a solntion of twenty grains of muriate 
t}f Inrytes in more than half a wine-glass of pure 
wnter : dtp the point of a straw into a phial con- 
toiniug flulphuric acid and Immerac it in (be wine- 
glass. The whole liquid will become white like 
milk, thin precipitate will soon fall to the bottom, 
being heavy and very ioootuble. Here the sul- 
phuric acid suddenly seizes upon the barytcs ; 
forming sulphate of birytes : at the same time 
ilriviug off the muriatic acid. Thu vnpour of the 
Utter may be identified by holdutg the nose over 
the glass at the instant of docompositiDn. This 
cxpdrimeot may be reversed by adding some of the 
sotution of muriate of barytes to a gloss of very 
diluted kulphuric acid. 

ThiU for Lime. — Into any transparent: liquid 
savpected to contain lime, pour a few drops uf a 
solution of fluntc of ammonia : a plenti^il white 
precipitate of fluatc of lime (Derbyshire Spur) 
will fall down in the liquid. 

Poor into a solutioD of lime in any acid (muriatic 
for example,) some of the eolation of oxalate of 
ammonia ; an immediate precipitation will take 
place of an insoluble salt : the oxalate of lime ; 
muriate of ammonia will be held in solution. It 
is more proper and convenient to use the oxalic 
acid in combination with ammonia, as this alkali 
•errea to saturate the acid which has been jost 
disengaged from the lime : otherwise this add, if 
in excess, will redissolve the lime. Oxalat« of 
potttt also is an excellent tfst for lime. 

TtKtJhr Sii/phate of Lead in Sulphuric Acid. — 
Aa sulphuric acid, in ihe large way, is mode by 
combustion of sulphur with nitrate of potasa in 
leaden chambers, the >>upctfici3l parts of the lead 
•lie often diMolved by it ; thus forming sulphate of 
lead, small portions of which are held in solution 
by the acid, when sold in the shops. To detect 
this Adulteration, pour a drachm of the acid into a 
tumbler of distilled water ; if a white precipitate 
falls down, it is a proof of the presence of lead. 
The affinity of water for sulphuric acid is the cause 
of this precipitation. 

Tett/or Sviphaie of Lime m H^'a/rr.— Although 
sulphate of lime Is so insoluble a salt, that an ounce 
of cold water will hardly diHsolre one grain of it, 
still it is surprising, what qusntitiea of it are held in 
solution in great bodien of witter. To discorer this 
salt, add to a tumbler of Tbamrs, or New River 
water, a drschni of the solution of carbonate of' 
potasx. An nhondant precipitate of carbonate of 
lime will insuntly take place. Here there Ls an 
in»tance of douhln Heromposition : the carbonic 
acid combining with the lime, and the sulphuric 




acid quitting the lime for the potasa. 
nate of lime being very insotul)le is predpj 
and the fulphate of potiM being aoluUe 
rrmaiiis in the clear liquid. lo analyi 
waters, carbonate of potass is oil exeeUeot- 
accoont of this property of rendering 
if they contain sulphate of lime. 

General Te»t for the Metatlit Satis.— Xx 
solution where a mrtal is suspected to exist lo 
binatioii, jiour a few drops of prussiste of p 
stir the mixture. If a precipitate falls down, 
proof of the presence of wme metal, as thi 
hns not the power of precipitating salts, of 
the earths form component parts. The ooik 
quantity of the precipitate will serve wit 
asaiatance of future tests, to demot 
and nature of the metaL 



MISCEUANIES. 



New Method qf Taking a Fae-timik.~-'?i 
piece of white paper on the inside bottom 
porcelain plate ; write upon this paper with 
mon ink, and before it is dry sprinkle apos I 
fine powder of gum-arabic, which will afford a 
reliff. ^^Tien the ink is dry, brush off the * 
ftuotts gum, and pour into the plate a i 
compound of 8 parts bismuth, 7 of lead, m 
till ; which is fusible at the boiling tempersti 
water. Cool it rapidly, to prevent crystallii 
Acounler-impre9sionaf the writing is thus obO 
and by dismlving off the ^m in tepid wati 
pUtc presents characters, which viewed by t 
are very legible and beautiful. Prom this pla 
means of common printing ink, true Cacsinu 
the original writing may be produced. ¥1 
already dry may be copied In the same w« 
going over the letters with a pen dipped In ■ 
weak solution of gum — then sprinkling it wil 
powder, and proceeding ai before. The on! 
quisite precaution in this metallo-gniphic ope 
is, that the metallic plate must be of an even 
ness, and that the surface on which the cfaiur 
are traced must be periiectly smooth. 

Pretervaiion <if WalUfmm Dampnem.' 
position of one part wax, and three 
previously boiled, with a tenth of its 
litharge, spread over a wall in a melted strtt 
durable and efTectual preserrativp from iiya 
dampness. When this coating is to be i]VMd 
stone, or other porous matter, it should be I 
once or twice previously, which may be accooip 
by the pnrtiol application of a portable fbi 
Tbe composition is then more efTectually ah«< 
Surftces of plaster or gypsum, suob as wnlU. I 
reliefs. &c., may in the same manner be prea 
from injury. If the cost of wax la an obj< 
importance, resin may be osedas a substituta. 
part of drying oil, and two or three parts of i 
form a amiable composidon. They may be n 
together in an iron or earthen veaocl, taking a 
manage the heat so as to prevent boiling 
Statues of plaster may be safely exposed ti 
weather, if well covered with this cement, a 
the Utter bo mixed or compounded with mc 
soap, various colora may be given to the staUii 
OS to make it resemble marble and other dn 
materials. 



be char 



lAVitOTf:— Prtntoil by O. roAxcia, S, Whtta Hunt Luw, MiU End.— Publi«bml by W. BatiiAta, I 



ll.pAlcmostodB 



170 



MAGAZINE OF SCIENCE. 



COUNT VAL MARINO'S PATENT FOR 
MAKING GAS FROM TAR, Ac 

"Mt iDTCDtion relates, first, to a ciode of manufac- 
tming s*» for the purpose of light, ^m eotl and 
other Ur and oils, and other fatty nutters, together 
with water ; and, 

Secoodiy. my invention relates to an improred 
omuigemciit or construction of apparatus or burner 
fur consuming gas for the purpose of light. And. in 
order to give the best iufurnuLtloa in my power, 1 
will describe the apparatns aaed and the proceu 
pursued by roe In carryia^ oat my inTentiun. And 
1 would first remark, that it ia well known that in 
COfiTerting tor, oils, and other fatty matters into gas 
for the purposes of light, owing to the excess of 
carbon it contains, and the roiKsefiueiit want of by* 
drogen and oxygen in converting such mnttcrs into 
gas for the purpose of hght. much of the carbon 
conUini-d therein cannot be beneficially employed ; 
but it is in fact lo«it in the process of deeoinpoaitioQ, 
owing to the want of a safficient dose of hydrogen 
and oxygen in order to convert th« whole of the 
■ carbon into carburcttad hydrogen. And in order to 
make up for such itoficienry of hydrogen nnd oxy- 
gen, riHtuijtite for fully saturating the carbon con- 
tained in the tar, or iu uny particular oil or fatty 
matter, recourse has been had to the decomposition 
of water, in order to supply »uch deficiency of hy* 
dmgen and oxygen ; but up to the present time 
such proc«>8es have not; 1 believe, been snccessful. 
oning tn the nature of the procc«ta pursued and the 
epparatus employed. 

Now the first part Of my invention has for it« 
object a mode of decomposing tar, oils, uid other 
fotty matters, and also water, whereby I am enabled 
to obtain a more complete combinalion of the gases 
evolved, and consequently a more beneficial result 
than heretofore has been accompliafaed. And such 
is the oature of the appArninit nnd process, that the 
tar, oil, or fntty matter rtnpluyed is fully decomposed 
by being closed to highly heated surfaces of coke 
or charcunl, and the water is also fully decomposed 
la taitablc vcuela or vessel, and acted on by highly 
boated coke or charcoal ur surfaces. The gas pro- 
ducts of the water are, when fully effected, brought 
into a highly heated retort, or such like veaiiel, tilled 
with ookeorcharctxil, wherein the decomposing nl 
the tar* olUi or fatty matters are going on, and by 
this process, such is the chemical ocLiim and re- 
action of the gases that the cnrb<m ooutained in the 
tar. oiU, or fatty matters osed, becomes fully satu- 
rated, ond thus may he obtained the whole, or very 
nearly (be whole of the carbon, in the state of car- 
burctted hydrogen gas. It is well known that 
dilTerent tars, oils, ainl other futty matters evolve, 
when decomposed, different relative qnantttiM of 
carbon, hydrogrn. and oxygen, consequently require 
the de<»mpnsition of more or less water to moke 
up the deficiency, by supplying hydrogen and oxy- 
gen sufficient to Mturatc the excess of carbon, in 
order, under the most fivorable circumstonoet, to 
produce carburcttcd hydrogen gas for the purposes 
of light. Care must therefore be observcNd in 
making carburettcd hydrogen gas from tar, or fl-om 
particular oiU. or from other fatty matters, to ascer- 
tain how much water tlio Mme will require to have 
decomposed. But as an analysis of all, or almost 
all of such matten U to be found to most modern 
chemical works, it will not be necessary to «nter 
more at Urge into this subject, further ihan to re- 
niork, that i atom of carburettcd hydrogca oon- 



ststa of 2 atom* of cwboB, and 3 ataoi 
hydrogen ; 1 stum of oxide of caeton, aa 
of 2 atoms of carbon and 1 tloa of oxygoi 
M water, when dvcompuaed, j>rodaoee 12 per 
of hydrogen, and the rest oxygen, it follows 
having aieertaUed the quantity of carbon, h 
gen, and oxygen contained in the particnlas t 
about to be employed La the maoufactuFc a 
the ijuantity of water required to be decompor 
iDoke op the deficiency of hydrogen and oxjge 
be immediately known. And I would fiiTtku 
mark, that in order to fully amA moat bend 
perform my invention, it la of importance th 
retorts or apparatos employed, should be k> 
on uniform heat, that U, «c a bright white-red 

Denription of the Drmrwng. — The rfn 
Fig. 1, represents the section of three rcrtiff 
torts, suitably arranged for performing my invei 
and the furnace is suitably constructed for C 
niently heating and maintaining the same atti 
form temperature; A, B, and C, bring the 
retorts, one fur decomposing the tar or oil, or 
fatty matter employed, another for decompooii 
water, and a tliird for continuing the prodll 
the vrater. It is not however material which 
retorts are used for the separate daties, they 
all similar. In the arrangement shown, A 
retort in »hich the water is decomposed; '. 
retort in which the tar or oil, or other fatty x 
is decomposed ; and C is the returt into vitii 
gases cTobred in the retort A enter, and are fi 
deeomposed, the object being folly to decoi 
the water before the products thereof come in 
retort B, to combine with the pnoducti of the 
retort. D is a vessel containing tar or oil, or 
fatty matter ; aud E is a rcMd containing - 
under which are 2 syphon pipes, which ente 
the upper parts of the retorts A and B ; and 
are cocki on the Tesseb, D and E, to r^fiibl 
supply. The nature of the retorts, which i 
cast iron, is clearly shown in the drawing, 
retort baviog a projecting or deeceuding tu 
connected at the lower end thereof, within whl 
grating*, which are similar to fire-bora, a 
raised and lowered, and the coke or charooftl . 
retortd rests on tliese gratings, which bUow * 
passage of any small ashes or dost uf the oott 

The pipes. Fig. 3, connect the retorts, A A 
and B and C, as is clearly shown in the dm 
and in using this a]>paratus the three retort 
filled from above, with coke or charcoa], 
then the cndi of the retorts are to be 
and all things arranged, oe shown in the di»w 

I would here remark* that although I 
that the retort, C, should contain charco 
coke, thu is not absolutely necessary, and it s 
be understood, that I prefer the nse of oo 
contequencr of its cheapness, and the rctoH 
cliargcd with fresh coke every 21 hours ; aad ] 
found thnt I am thereby enediled to retain the 
pcraCurc required more reailily, (he retorts be 
a good red-whituhcat, the tar or oil. or fatty s; 
oxid also the water, is to be permitted *o flon 
serving thot tlie water ia allowed to drop, ix 
portion to the requirement of the other ir 
employed ; and as it It difl&oult to arrange appi 
to perform this operation with nicety, anid < 
syphon tubes might become more or less stopj 
worlcing, the simplest and the best practical I 
I am acquainted with for regulating the cnpf 
water Co the rvqujiw atmts of the mslter 




MAGAZITTE OF SCIENCE. 



171 



It 



itoa 



Uf bCed gu burner sear the retort, and 
ot Uie workman, hjr this meana he will, 
tu titae, bt enabled to observe whether 
uf his working im aecording to the desired 
obaerrea that tlie dftme becomes 
if proper, it will indicate that too 
Itmng lapplied, and by this simple 
woritinan baviag onoe Kt it right, the 
go OH correctly, unleM some impctli- 
' offered to the supply of tlie matter employed 
iter. There is a pipe attached to the retort 
to the ^somctcr, for it shouhl be under- 
carburetted hydroj^en gas thui mannroc- 
not mjuire panning, which is an 
sdvantiiga mppeiiaioing to thii mode of 
shouid be itated that tbe mntCer I 
iploy, and according to the coat of the 
above mentioned, will, 1 beliero, be 
ii coal-tar ; and I would obaerve 
I prefisr the arningcmeat of apparataa 
for the purpose of decooipotting 
and water employed, 1 do not cootine 
I, provided the mode and process of 
retaiord as hn^cin described. 

proceed to dcfcribe the second port 
ition. 
iws an extemnl new of a gas-burner 
for consuming gas, constructed ac- 
Ihis p»rt of my inrcntion ; and 
_ is • section thereof. On examining the 
ft it will be seen tliat the outer sur^ce of 

Er part of the burner, a, is coned, u 
from m to a, la other rcBprcta it ifi of the 
conalruetion : and A, is an outer cone 
rries the gallery for the glass cbimru'T, 
[|nmtly tlie lupply of air for the external 
|r tfame will pains between the burner, th and 
6 .- and, owing to the upper part of the 
ig in the form of a cone, the air wiU 
a dire^lion to pass through the flame, 
effect a more perfect cuinbuHtioa 
>Ued to such arrangement of apparatus. 
b« remarked^ that I am aware Uiat 
idrical bnmen have before been used, 
in with an external cone, very similar 
not claim the using of such cone un- 
wlth a coned figure of the outer upper 
at the boroer, as above explained. 

thus described the nature of ray Invcn- 

the manner of performing the aarae, 1 

lark that what I claim, is, first, the mode 

ribed of manufacturing carburelted 

-gas, from tar, oil, or other* Cutty matt^TS, 

decomposing the water, before the 

diereor are permitted to enter into that 

the. apparatus, wlierein, the tar, oil^ or 

matter is decompoied, imd causing the 

•r oombiaed products to paaa in contact 

~ surfaces. 

ly^ I claim the method of coDstructing the 

for oonsaoiiog gas, aa hereiu described. 



NEW ZEAUVND FLAX. 

tenor of nAturalists* Ita eom- 
has been acquired from the circam* 
matives of New j^ealand employing it 
tvre of their apparel, cordage, and sll 
for which hemp aiui (\ax arc used in 
The atrength of its tibros, how- 



ever, greatly exceeds those of the last-meatioaad 
vegetable substances; and, indeed, oearlyapproschaa 
the tenacity of ailit. Of this plant there are two 
sorts, — one bearing a red flower, the other a 
yellow. The leaves of both are similar to those of 
ttie common aloe, bnt the flowers are smaller, and 
the clu5ters more numerous. The Z«ulandeni 
obtJiin the flax from them by very simple and expe- 
ditioua mouua. The fibrca are beautifully (ino, and 
white, shining like silk ; the cordage made trom U 
was fonnd by our navigators to be very mudi 
stronger than any thing we could produce with 
hemp. With the view of introduoinii; tlic growth of 
so vahiablo a plant in this conntry. Captain Fer- 
neaux brought over some of tlur seeds, which were 
sown in fCew Garden*, by order of Us late Mnjeiity, 
but aofortunniely failed. Subaeqvent \o this 
period, the cultare has been very succenfuUy pDr> 
sued by our settlers in New Soutli Wales, We art 
indebted to Mr. William Salisbury, of Hromptonf 
fur th« discovery of this ideuttial plant, growing 
indigenously in- the south of Ireland, when it 
flourishes luxuriously.*^ This- discoverr will pro- 
bably' prove, ultimatelVf of the utmost iru|>ortano« 
to Ireland, where the poor may be profitably em- 
ployed, both in the culture and subst^tjufuit niauu- 
faeturc. Mr. Salis^bury observes, that plants oC 
three years old, will, on an average, yield thirty- 
six leaves, besides a very considcmble increase of 
ofl'-sets ; which leaves being cut down, at the time 
of L-lcAring the cjunrters in the niitumo, are found 
to spring up again in the following summer. 

Hcspecting the produce, tite same geotlcaaa' 
states, " Six leaves have produced me one otmoc 
of Hlires, when scutched p^^rfectly clean and dry; 
at which, an acre of laud planted with thb rmp, at 
three feet distance from plant to plant, will yield 
mthrr marc than sixteim Imndred wri^ht per acre*, 
which is a very great produce compared with that of 
hemp or flnt. New Zealand dux may be scutched 
with little labour or trouble, oud miiy be performed 
by freraons in rommnn. The leaves should l»c cut 
when full grown, and macerated for a few days la 
sLacrtmut water, and then passed nnder a roller 
machine properly weighted ; by this process the 
fibres become separali^d, and if washed in n running 
stream, will Instantly become white. Ulicn the 
fibres ure thus scutched clean and dry, any Ictod of 
friction will cause them (o divide into any degree of 
fineness in the harlr, so far even, as to cottontze : 
whereby it is fitted to all the pnrpoaes tu which 
hemp and flax are substituted..'* 

This plant is, at present, nnder onltivatiAn iiv 
several parts of England nnd. Wales, It will grow 
in either a uioi<it or a dry soil ; on a hill, or in ■ 
valley, but roost luxuriously where there la aa 
abundance of moisture. 

< Thi« U an error, tlMplnai to ovt Inillgtnioui to Inriaofl. 



CAII3E OP ELECTRO-MAGNETIC 
ACTION- 

Thk object of the prrsent, oar first pnper relativ* 
to the subject of electro-magnetism, is to convey a 
brief, but comprehensive view of the scientific 
principles upon which the deflections and rotations, 
which it is the object of its experiments to exhibit, 
rhiefly depend, leaving their further illuatratioD to 
future opportunities ; giving, however, a sufficiait 
explanation of its laws to enable our readers to 
understand the reasoD of the effects they wiloa»» 



172 



lAAGAZINE OF SCIENCE.. 



mod to cslcnUte before-band the rrfuU of lucfa 
wnhinin aa they may b« consCructiQ^. 

It is finl to be reniarkecl, that the ran or some 
Other caoM, u constantly eiertins neb an infliurnce 
vpoa the tropical n^ona, as to occajioo a cnirent 
of electricity to pua around the earth from ea*t to 
west. In conaeqoenoe the magnet Is diverted from 
this conrae, and takes a direction of north and 
•onth. What exiita in nature we can imitate arti- 
ficially, and if an electrical current be made to poss 
along a wire, it forms around that wire an electrical 
atmoapbere. If a magnet be ploced witUin tliis 
almoapheret and be left free to more, it will turn 
round until it vUnda across the electrical current — 
the north pole being In a certain direction, according 
to the way in which the fluid traverses. If there 
be several magnets, they will also ail turn their 
BOith poles the same wsy, and if there be no mag- 
nets at all, yet the conducting wire itself, will for 
the time be in the same condition — one side of it 
being north, the other side of it south. 

This will be easily understood, and lead us to con- 
sider the effect of two wires upon ea^ other, when 
conveying the fluid along them. 




Let A B C D be two wires, conveying the fluid 
•long them in the direction of the arrows — the 
nsgnets vrill stand as represented, the north pole 
being above the wire in both instances. Now take 
away the mogncta, and suppose the wires themseWeB 
to be influeocod in like manner — the upper part of 
each wire will be north ; therefore, the parts of the 
wire nearest to each other wUl be in ilifferent stotes 
—one south, the otlier nortli, consequently they 
will attract each other. Thus two wires conveying 
the fluid in tJic same direction attract each other, 
and if they convey the fluid in op|>osi!c directions 
thry will repel each other, (see the annexed cut,) 
to which the two south poles are opposed to each 
other. 

If the conveying vrirea are oblique to each other, 
they have a tendency to arrange themselves parallel 
to each other, lo the anDezed, it will be seen that at 




the ends the noKh and soalh will attract esch other, 
having a tendency to dimtDish the angle between 
them. At the httnt^ time at the top and bottom tli^ 
iwo north poles and the two sooth poles arc opposeif, 



and comsrqoeiitly repel cadi other, 
increase the angle between them. Agoii 
the fluid in the wire C D be coavvyiwi iaj 
trary direction, (see Pig.) tiu e&ot 



contrary, nntil the wires stand at right angja 
they will follow the law as before. This la 
be applied to explain fllcotro* magnetic rt 
Suppose a wire A D, and another itirr, A O' 
suspended near it. When in the positioD j 
the fluid flon-ing from the centre eastward, tl 
be attracted by the wire A B, and that eni 
which is free to move woold move to the wiq 
it gets to O, and when here a double force] 
forward, for now S is attracted by N, and N 



>Qk 



CI 



Bttr 



by N,nntil when it gcts^ again to its hoi 
tion, when there is only rrpuliioo between N 
This, however, would continue to act, un 
moveable wire reach the zenith, when atti 
b<^ns as at first. This, however, would r 
Immense force. To assist the attractive i 
then of the wire, we bend it up at each end, 
to be nearer to the moving wire ; and if we i 
to have the greatest etfect we must move it til 
quite round the moving wire, -and we ihal 
have an equal sttroction of the one side, ai 
pulsion on the other to move it rouott. i 
course continued rotation will be t\\e rtr-si 




iVb/<*.— Be it observed, that this wUloi 
motion in a horizontal wire, or one ini 
the magnetic meridian, but not a vdre m( 
tlcally. 

7*liis rosy be explained as follows i 
neit Fig. n^resent a roil of wire puttint; 
the horizontal mni^nrt within it : it will 
flucncc the wire, hut if the. wire were 



MAGAZINE OF SCIENCE. 



173 




oultl attract erery vertical tcction of that 
•uppose a ckdetoti frame inaile of a 
▼•rtical wirc», the coU woulil attract 
of each wire< 




pirt of the coil being taken, wc shall 

acCioQ njion one [lartirle of Ui« wire O. 

It O u tttrncted Co O with a certain force 

repelled from E with the force O I. Then 

ilutiun uf forces the point O wlU proceed 

wLe angle of the pju-allelogram made up 

forcea, or Co B, The same is the effect 

•pon any other particle of the wire O. 

me dimini&Ltiig in intensity as U approaches 

ctt/e, that being the point most distant from 




(MOTION AKO LOCOMOTIVE 
MACHINERY. 

maehines, to be mored by hnman 

have loDi; desired tu iUustrute ; but the 

of all Chat ffc could |)rncDre a sight or 

has shown tltnt the task would be 

rccly tucful, such ignorance of the 

anics do most of tbein exhibit. We 

seremJ Bcfaetnes of thift kind sahmitted to 

harv declined their insertion, because we 

been obliged to have pointed out their 

on also; and it would have been an 

ploynit*at to displi; the faolts of Chose 

wished to contribute to the utility of our 

to whom onr thanks w<;re therefore due. 

aware that sereral friends and corrcspon- 

at work in hoprs of accomplishing tbo 

m of a manumotivc carriage; but before 

UieU tinw atid nooey, we trust (hry will 



tbo following fects ; first premising that ■ 
manumotiTe carriage is understood to be one where- 
by a person may more himself with more rapidity, 
and less labor, Uian in walking, and that for a oon- 
Cinuance of time. 

By Cite action of Che feet apon treadles is one way 
of Bcrompli.^hing this, the body sitting down. It is 
cridcut that cTery step lengthens ont one leg, to 
propel the treadle to itn fullest distance, nnd draws 
up the other leg to begin the next step or strokCi 
and tliis alternately : when tlie knee is bent the 
muscles exert but little force, and it is only when 
the leg becomes nearly straight, that the strongest 
of them come into action at all ; were it not so this 
alteruate, ruptd. and powerful actiun, would in n 
Tcry few minutes occasion intense fstigue in the 
legs, and might very likely snap the tendon AchU* 
les, or great muscle of the leg, 

The second method proposed is assisting the ac- 
tion of the treadles by the weight of the body. The 
action ia standing first npon one trendic, and when 
that ia pressed down stepping upon the cilht-r, ond 
n altemately. In this Uie body ia tirted up a foot 
or more at each step (see the Aellopodes. vol. I.) 
This is the case in working at o tread-mill, and 
although a con^ide^al)le effect is produced, yet it fs 
not lasting. It is writ known that the ntmitst time 
human strength can sustain this labor efficiently iq 
ten or twelre minutes. A projector may lay. thaC 
in twelre minutes a great space may be passed 
OTcr ; this is true, if the marhine be wrll coa> 
structed, and ruimiag upon the Ice, or even on ii 
smooth board, or a railroad : but it will be remem- 
bered, that the more rapid the motion the greater 
the fntiguc. 

A third method is by means of a winch turned by 
the hands: this is subjt-ct to the imperfcctioas of 
the last scheme, and a few others -. though human 
power is better applied here tlian by tho action of 
the feet, and could the action be continued for any 
length of time, a winch might be snccvB'ful ; but it 
cannot, the mueclcs of the arms become fatigued, as 
in the former iuat;incea. 

A fourth method has been proposed, similar to 
the taction of a pump-handle : the fault is the same 
as before, the short duration of available power: 
and this is the sticking place of all locomotive pro- 
jectors. 

We hare been often asked for our advice upon 
this matter, and give it freely: 1st. Let our friends 
avoid all wheels, joints, straps, levers. &c. that can 
by posaibility be done vrithout. Make the machine 
as light in weight as possible ; have it upon three 
wheels, the first of them a guide wheel, and let the 
motive action be that of rotchiff, and thi« for two 
very essential reasons: Ist. Because the action of 
rowing can be lung continued, even for hours : and 
2nd. Because in it the strength of the muscles of the 
legs, the loins, and the arms, are all called into 
exercise, without any strain upon either, while the 
vreight of tlie body is supported by sitting. In ad- 
vising this method, it is to be remarked, that the 
BtTL'ngth of the arms is the greatest when pulling 
about three inches below the breast, and in nearly a 
straight line towards it ; both polUng at the same 
time, and tho feet aiding their action by their pres- 
sure against a board. The stroke for the hands may 
be about two feet six inches, or three feet ; and the 
hstndles or bar, or whatever else they may take hold 
of, muit not move in the nrc of a circle, unless of a 
very Lirgo one. We have little doubt, ttut npon 
this priuciplu elTeclivc locomotive machines may bt 



MAGAZINE OF SCIENCE 



conitru£tc(l, which will pui with considerable speed 
OD level groand ; and tbiuk thkt lurh a uarrUge 
wnuUl be of ossontuU nte, not iDrreljr for cxcrctiCi 
but for the conveyance of inteUIgeDce on raUwajri 
(Vom one post or station to aootber, in case of ac- 
cident, or similar necessity. 

The following apt remarks upoa loromotioa in 
grneral are abridged from Bingelow's Techaolo^, 
published in Boston in 1829. He says, 

" Thechirf obstacles which oppose locomotion, or 
change of place, are i^vitj and friction, the last of 
which is, in most cases, a consequenre of Lbe first. 
Gravity confines oU terrestrinl bodies sgainst the 
surface of the earth, with ■ force proportionate to 
the quantity of matter which composes them. Most 
kinds of mechanism, both natural and artificial, 
which assist locomotion, are arrangements for 
obviatinp; the effects of gravity and fViction. Auimats 
that walk, obviote frictiao by substituting points ^f 
their bodirs, instead of lurge surfaces, and upon 
these points ihcj turn, oa upon centres, for the 
length of ear.b step, raising themselves wholly or 
portly from the ground in sncceasiTe arcs, instead 
of draMHUg tbemHelves oloug the surface. As the 
iect move in separate lines, the body has also a lateral 
Tibratory mutiuu. A man, in waikinf!^ puts down 
one foot before the other is raised, but not in run- 
ning. Quadrupeds, in walking, have three feet 
upon the ground for most of the time; in trotting, 
only two. Animals which walk against gravity, as 
kke common fly, the tree-toad, &c., support 
tbemsclres by suction, uang cavities on the under 
side of their feet which they enlarge at plrasure, 
till the pressure of the otmoHphcro cnusea thi-m 
to adhere. In other reai>ect8, their lucomoUoQ 
if effected like that of other walking animals. Ilirdfl 
perform the motion of flying by striking the air 
with the broad surface of their wings, in a down- 
ward and backward direction, tlius propelling the 
body npward and forward. After each stroke, the 
wings are contracted, or slightly turned, to lessea 
their resistance to the atmosphere, then nlsedi 
and spread anew. The downward stroke, also, 
being more sudden than the upward, is more re. 
fisted by the atmosphere. The tail of birds 
■cTTcs as a rudder to direct the course npward or 
downward. Wlton a bird sails in the air without 
moving the wingii, it is dune in some cases by the 
velocity previonsiy acquired, and an oblique direction 
of the wings npward ; in others, by a gradual de- 
scent, with the wings slightly turned, in an obUquo 
direction, downward. Flshea, in swimming forward, 
■re propelled chiefly by strokes of the tail, the 
extremity of which being bent in an oblique posi- 
tion, propels the body forward and laterally at the 
same time. The lateral motion is corrected by the 
■Mat stroke, in the opposite direction, while the 
forward course continues. The fins serve partly to 
asaist in swimming, bat chiefly to balance the body, 
or keep it upright ; for, the centre of gravity being 
nearest the badt, a fish turns over, when it is dead 
Of disslded. The swimmiu^-blAdder, whirh ciisla 
In most fishes, though not in all, is suppo6ed to 
have an agency in adopting the specific gravity of 
the fiab to the particolar depth in which it resides. 
The cower of toe animal to rise or sink, by altering 
ih» waimioni of tlus organ, has been, with some 
rwMo, diapttted* Some other aqaatic sairools, ai 
Um^W, Ivim with a sinnous or undulating motioo 
td 0*9 body, In which several ports at once are made 
to act obliquely agalnat the water. Serpents, in hke 
Bwaacr, advaucc by mcuit of th« winding or Berreo- 



lit. , 

I 

paft 

le I 

nsk 

. ios 



tine direction which they give to their 

by which a succession of oblique forces 
to act Bgninst the groand. Sir Everard 
opinion that serpents use their ribs ht the] 
of legs, and propel the body forwards bjT ' 
the plates on the under surface of the 
successively, like feet against the gtomid. 
deduces from the anstoiny of the animal, 
the movements which he perceived in si 
large coluber to crawl over his band. Some 
and larvie of alow motion, eitend a part of 
body forwards, and draw up the rest to overli 
some performing this motion in a direct line, 
in cur^'cs. When land animals swim in wi 
are supported, because their whole weight, ' 
lungs expanded with air, is less than that ot{_ 
balk of water. The brad, however, or a paft 
must be kept above water, to enable the i 
to breathe ; and to effect this, and also to msk 
gresj in the water, the limbs are r-xe rtetl, in s 
sive impulses, against the flaid. Quadrui 
birds swim with less effort than man, be 
weight of the head, which la carried 
wsler, is in thcin, a smaller pro|Hirtional pi 
the whole than it ia in man. All animals an 
vided, by nature, with organs of loomutim 
adapted to tlu'ir i^lructurc and situotinn ; anil 
probable that no nnimo), man not being exc 
can exert his strength more advantageously b 
other than the natural mode, in moving himsci 
the common stirface of the ground. This n 
of course, does not apply to situations in 
friction is obvisted, as upon water, ice, rail- 
t^r. Thus walking cars, velocipedes, &c., alt 
they may enable a man to increase his ^ 
favorable situations, for a short time, 
actually require an increased eipendituro oj 
for the purpose of transporting the machine' 
use of, in addition to the weight of the body. 1 
however, a great additional load is to be transj 
with the body, a man, or animal, may dt:ri\« 
assistance from mechanical arrangementa. 
moving weights over the common ground, v\ 
ordinary asperities and inequalities of snbi 
and structure, no piece of inert mechanism 
favorably ndspted as the wheel- carriage. ] 
introduced into use in very early ages. V 
diminish friction, and also sormuunt obatsd 
inequalities of the road, with more- advsut 
iHKlies of any other form, in their place, 
Tlie friction is ihrninished by transferring' 
the surface of the ground to the centre of (he 
or, rather, to the place of contact betwec 
ailetree ond the boss of the whe«I ; so thai 
lessened by the mechanicn] advantage of tbs 
in the proportion which the diameter 
bears to the diameter of the wheel, 
surfaces, also, being kept polished, andj 
some unctuous substance, are in the 
condition to resist friction. In like manne 
common obstacles that present thenuelTca i 
public roads are surmounted by a wheel 
peculiar facility. As soon as the 
against a stone or sinulnr hard body, 
into a lever for lifting the load over 
object. If an obstacle «igfat or ten inches Is I 
were presented to the body o( « caniage unpit 
with wheels, it would atop its progreas, or sub 
to such violence u would endanger ita safety, 
by the action of a wheel, the load ia ''" 
centre of gravity passes over in the 
easy uro, the obetwlc fumiihiac 



. an 



wtsd 

(hti 
twee 
thai 
? of tbs 

.11 

: bntp! 



MAGAZINE OF SCIENCE. 



in 



lercr sets. RoHen pUced luider a hearj 
Hut frictioD in a greater degree thux 
they arc trur gpheres or cjliiiderSf 
OD which they are coostnuned to 
cjiindhcal roller occaaioDS friction, 
drruies In the least from a straight 
lanical adTanta^ ca of a wheel are 
to iu site, and the larger it is* the 
Irdoea icdiatiuigh the ordioary re- 
largc wheel will surmoant stones and 
better than a small one. since the 
on which the force acts is longer, 
de«crib«d by the centre of the load is 
a larger circle, and, of course, tlic ascent 
lual and easy. In passing over hole5, 
nations, also, a large wheel sinks less 
le, and consequently occanoni less 
iodltore of power. The wear also of 
less than that of small ones, for if 
a wheel to be three feet in cliamettir, it 
round twice, while one of six feet in dia. 
ruond once ; so that its tire will come 
in contact with the ground, and Its 
11 twice &5 often have 1>J support the weight 
I load. In practice, howcvt-r, it is found neces- 
l^confine the size of wheels within certain 
^btly because the tuateri^dj used would mnkc 
HF great sbe heavy and cumbersome, since 
l^rate part* would necessarily he of large pro- 
to hate ihu requisite strength, and partly 
woald be diKproportioned to the size of 
its employed in drnui^ht, and compel tliem 
iqoely downwards, and therefore to expend 
their force iu acting against the ground.** 



LITHOGRAPHY. 

(Htwumcd frwn page 131. J 

r. — The stone must bo well wi)>ed with a 
of linen ; Uiis is a very necesanry pre- 
'sa some dust or sand might still adhere to 
ir, in «hi(*h case the drawing would dis- 
\r iti those parts. 

iftaraaa must take great core that no 

ihstuces be allowed to como in contact 

% as these would iofalltbty mark in 

he must on no account touch the 

fingen, nor breathe upon tt. He 

cautinuii lest any spittle should fall on 

log, and it is necessary to lay a sheet of 

ler the hand to aToid any accident. 

may be made with lead pencil or black 
rnring that the impression will be the 
of the drawing. One may aIbo. to avoid 
; the drawing rCTcrsed, make a sketch on paper 
a soft T>enri), put it on the stone with the 
ing towards it, and pass it in the press ; by 
ktion the ikctch will be found traced on 

viabed to hare the sketch on the side 

to which it is drawn, tbe i>apcr must be 

itnd with red chnlk or black lead, and 

^lo the stone ; by pnsaiog a blunt ncctlie 

the lines of tbe drawing, the black lend 

on the other side will repeat them all on 

: to avoid dirtying tbe bock part of every 

paper, a acp&rate aheett rubbed with black 

be Uid between ttie dnwiag ud the 




It Is necessary to hsTC screral portcrayona ready 
with chalk in them, as, from the natare of the 
chaOc, it ia apt to get heated and aoftened by tbe 
wmrmth of thti hands. 

Dravring with Chali.—\t is well known that tbe 
surface of a stone, prepared for a chalk drawing is 
composed of innumerable little points, which file, 
u it were, the chalk, and receive on their sorfam 
small portions of it ; but, according to the second 
obflervAtion, some force must be employed to mako 
It adhere to the stone, and the greater the force tho 
more it will adhere : tho draftsman mnst conse- 
qnently take care to present to the stone those ports 
of the chalk which have tho greatc-rt degree of co- 
heston ; thus, instead of giving a sharp point to 
his pencils, be mast avoid cutting th<^m as macfa as 
possible ; and if he is forced to do so by the fineneaa 
of the lines, it is better to cut the pencil in tho 
shape of a wedge. 

Independently of the diflerent methods of catting 
the chalk, there ore also di6crent modes of holding 
it ; it may be brought from right to left, held ver- 
tically, inclined to the left, so that the point might 
follow last, or inclined to the right, so that its 
point might como tirst. Of all the different posi- 
tions of the pencil, this last is the one which causes 
the chalk to adhere the more strongly to tliu stone ; 
the more it is Inclined like an engraving tool, the 
more certain one will be that the chalk may hold. 
ta short, a better coroparison cannot be found than 
that of a sharp stick, which on being pushed with 
its point foremost on a rough floor, will catch every 
prutubemnce ; whereas, if it is merely dragged, It 
will slip on without any difficulty. IIiq chalk wilt 
also hold much better if the drafring is executed 
withnat going twice over the difiierent porta, par- 
ticularly with regard to the soft tints ; for each 
elevation of the stone being c^harged with diSerent 
particles of chalk, these cannot adhere so well as 
when the whole quantity of chalk is hiid oo at once. 
Thus it is evident that a drawing which is eiecuted 
la a free and bold manner must he more successful 
than one which is often re<toached. 

The pencil being cut in tbe shape of a wedgCt 
the stone well covered with paper, the distanc?es 
may be firm in the hand, although it may be In- 
tended to touch the stone but slightly. ^V hen the 
point of the pencil is tamed np by drawing, that 
part uiu»t be taken off with the fingers, as the firm 
port of the chalk alone must touch the stone. 

Didereot methods may he employed to correct a 
drawing : if it is wished to make a dark line fniuter, 
parts of it may be picked out with tbe point of 
the scraper ; if a line is to be completely scratched 
out. the sharp part must be employed ; but this 
must only he done in cose it is not intended to draw 
on that port again, as this operation destroys the 
grain of the stone : if a considerable portion of tho 
drawing is to he rubbed out, the glass muUer and 
fine sand must be made use of. 

DravtHff tvith ink. — Ink drawings may be exe- 
cuted with tlie hair pencil or steel pen, occordix^ 
to the style it is intended to imitate. 

The hair pencil ia used for all line drawings, 
writing, ornaments, maps, and landscapes ; of all 
the instruments employed for these purposes tliis Is 
the most useful : with the bnish one may imitate 
the finest engraving, and tho most delicate and 
sharp lines. 

The steel pen is for from being equally good, but 
as it is more expeditious, it is often employed, 
particularly for broftd touches ; in short, the nuthe- 



176 



MAGAZINE OF SCIENCE. 



ffiHf*<rtal stoel pen U OMd for bU straight luic«, and 
partumlarly for plans. 

Whateirer may be the nature of the drawing 
which is to be execnted with lithographii: ink, the 
stone may alvrays be employed as it cornea from the 
workman'i hands ; consetiuently, there ciiita a 
ffTcat difference between the prcpnrntioo of stones 
for ink and for chalk drawings, siace in the former 
cue the whole snrface must b« equally polished, 
while in the latter, the grato ought to be di0creut 
in different parts. 

As it is indispeosable that the lines of an ink 
drawing sh<jiiJd be as neat snd as pur? as potaible, 
it is necessary that the stone should linve tlie 
highest poasible polish. Soft lithographic stones 
are not good for ink drawings, on they are liable to 
be scratched by the steel pena, and in jrcncnd the 
hardest stones are by far the be«t : the delicate 
lines in ink drawings, nnd the light tints in chalk 
drawingSi print much better with these. 

(To he CQtitiniifd.J 



PREPARATION OF PIGMENTS. 

(Rtmsned from paffe \iS.J 

aSD COLOBS. 

Orange CMromate of Leadt or SHh-chnrntnte ^f 
hmd. — This color is not so bright as the miniutn 
and realgar ; but it is more lasting than ycllaw 
chrome. The action of the oils is aln-ays too great 
upon the oxides of Icsid to allow of this color being 
quite perraaneDt ; it should therefore be used with 
caution in those draperies where It^ changing would 
not be of much importance. 

Mfuncot, (Protoxidt of Xffld.)— The substances 
which are sold in the shops, under the name of 
massicot, are only ceruse more or less calcined, and 
are named light, yellow, or gold colored. Genuine 
massicot is the strongest oxide of lead, (protoxide ;} 
its color is a dull orange yellow. 

In the preparation of minium the lead is calcined 
in a rcrerberatory furnace ; this process gives a 
TQixture of masnicot and lead ; these arc separated 
by washing and trituration ; the massicot b«ng 
much lighter remains suspended in the water ; it is 
drawn off, and left to settle ; the deporitum which 
it then forms is collected and dried, and this is tlte 
true mnssicot. ]t may be employed with advantage 
in preparing the drying oils ; it produces the same 
effect as litharge when very finely ground. 

It may also be employed as a color : its tint is 
not brilliant ; but as it is a better drier than white 
lead, it may be suhstitntcd for it in mixing with 
colon which dry with difficxUty, as the lakes and 
the bituminous earths. 

ilfinium. — A higher degree of oxidation trans- 
forms the massicot into minium. (>n a large scale 
miniun is prepared by calcining massicot in nvcr- 
beratory nimaces ; it becomes first of a dark orange 
color, then purple, but this last tint disappears on 
its cooling ; when at this point, the doors of the 
furnaces are closed, but not hermetically, so as to 
allow of a little air entering. The mBBficot ooola 
Tcry filowly ; and, ox it absorbs the oiygen of the 
air, it becomes of a atrong orange color, and grows 
finer in proportion to the slowness of its cooling. 

If, inste-ad of massicot, we calcine c«msc, a pe* 
ctiliar red, called ** mincnU orange," is obtained, 
it b • minfom, bat of a tint more pure and brilliant 
than anj of its claaf. 



poaad oU 
-atioattH 

be nflm 



C%Hnabar, — This U also called rcrmi 
the Italian word vermiglio, (little wona,)J 
the kermea, <'rocciw itieitj which wia 
scarlet dye before the diacoTCry <tf Al 
duccd the cochineal. 

Cinnabar is composed of mercury and 
(snlphuret of mercury,) very intimately oomb 
It is found naturally formed in the quick) 
mines ; but that whwh is naed in ptfaitSvl 
artificial production. In Germany and tu 
cinnabar is prepared by diaaolving one part ol 
phur, and adding to it gradually five or six mi 
mercury ; the mixture bw»mes hhick, takei 
name of jflthiops mineral, or black sulphnri 
mercury; this subntsncc is then redvced to 
der, and sublimed in appropriate Tfltli, wl 
crystallized mass is obtained, com] 
filaments of a violet tint ; by trilaratioa H 
of a scarlet color. . 

But the mere grinding will not be 
give a bright tone to the dnoabar ; various net 
are employed for that pu/poae, which are 
generally known. Some maDofactaren grind 
ingredients up with plain water or with urine, 
afterwards boil it for aome time ; others tn 
with nitric acid ; hut it does not happen that 
of the method! hitherto employed for heighu 
the color of cinnabar, obtained by sublimatJoHi 
the same brightness as the Chinese TermiUioa, 
preparation of which is not Imown. 

BnehoU has obtained some cinnabar of a 
fine description by digesting the following ml 
in a sand bath,— one part of floor of sulphor, 
parts of mercury, and throe of potaaa. £sii 
in six pints of water ; this compound first ( 
black Bulphar, and, when the digestion is proki 
the red color developes itself. The operatioa i 
be much shortened by only adding the aolotia 
potass in small portions, to give to the mtxtm 
coonstency of thin psste, and supplied aa 
required by evaporation, and this, ai 
combination, are facilitated by being 
stantly by a glasa tube.' 

It ia not required to have a precise qnantii 
potass ; a greater portion than may be reqidn 
this liquid is placed near the Tcsacl, and nm 
a spoon as occasion may require. By thia 
sevend pounds of mercury may be convc 
Vermillion. The longer the hnt of the fii 
up, the more strongly the color will 
carmine tint. If it be requisite to have it of « 
shade, the fire must be moderated immi 
the color begins to develope itself. 

It la very injurious for those employed, 
mercurial vapours ; for which reason this 
should be performed only in a place wkure 
chimney has a good current of air t there 
should be fixed to the tube of gloss with whid 
mixture is stirred a staff sufficiently long to he 
good distance from the reseel ; in the same wa 
spoon should be lengthened with which tho. ■ 
is added. ^| 

When the color hat attidned the shade f|| 
the vcrmillioD is thrown into a small vat or 
full of water, and it is waahed until all the snip] 
of potaaa is carried ofl*. Hie advaatagea de 
from this pror(v>ding are, that it produces In a 
time vcrmilliun finely prepared, and of the ptiti 
shade required. 

(Th le emmmutd.J 



d aa n 
wed 

atiii^ 

l]TlUtil 

reqidn 
naod 

tiia M 

rl 

tof « 
ledia^l 



L««»o«i— (*rUi(Ml by D. FaaMcu. •, WkU* llona Un», Mil* Eod.— l>DtiUri»MS bj W, Brittau, II, Pat 



lAGAZINE OF SCIENCE, 



THK 



^titi Retool of nm* 



«CMBK« LXXV.] 



SECOND EDITION. 



Fig, 1 



[Prio \id. 




178 



^rACA^INE of scienck. 



ABEUTED WATERS. 

Tuia term i* pfJitularly applied to a Tarietj of 
adtlulnufi and olkaliae bevcro^s, more or less im- 
ppreguatctl with Axed air, or carbonic aeid ga», and 
u tbe manafactum of these liquids tuu of late years 
become of considerable utcnt, owing to their agree- 
able aa well as medicinal properties, we parpoae 
Ueacribing some ingenious apparatneefl that have 
Jheen used, or are still rniploypd, for that purpose. 
Water absorha unilrr tlir natural pressure of the 
ttnosphrre about it3 own bulk or volume of car- 
bonic acid gas. If a pressure be applied equal to 
two atmo<<|ihere8, the wiiter will ubflorb doubiti itd 
own Tolunie, its absorbing power inonuutag aa the 
preuurr. MTater thus impregnated acquires a 
pleasant arid taste, to which is usually added a small 
qunotity of potash or soda, aud luch flavouring or 
other ingredicnu aa may be required to imiute the 
iiataral mineral waters, or other more favorite 
bcremges, as ginger beer, lemouadc, ftx., and as 
such sold in the shops, streets. &c. An apparatus 
of great siinplicity, And ndapted to operating upon 
00 extended scale, b dLlioeaicd iu Figure 1. 

A is a strong plank on which the vessels are fixed ; 
B is a bottle, containing a quantity of pulverised 
cjtrboaate of Ume or chalk ; C is the tubulure and 
atnjijier of the bottle ; D a bent tube for conveying 
the gas into the bellows E, which nrc supported by 
the upright stand P ; G is a stop-cock connectml 
with the tube D, which pofiscs from thence into tite 
alrung irun-hou{)ed air-tight barrel H, susjteudeil by 
its axis on the upright pillars 11. In using this 
apparatus, the cask is to be half flUed with distilled 
or spring water ; the hole at the top is then to be 
stopped air-tight with a good bung, which is to be 
fastened down by means of the jointed strap or 
tuup L, being passed over the staple, and secured 
by a holt or key put through the same. Then pour 
through the tubulure of the bottle »ome sulphuric 
icid, diluted with live or six timt-s its weight of 
WHter, over the cliolk, and close the aperture by the 
screw-stopper C. Having taken otf tlie weight 
from the bt^Uows, the carbnuic acid extricated from 
the chalk by the action of the acid, poMk-s out of 
the bottle into the brltows, through thn tube D, 
which hug an orllicc oi.enin^ under them. When 
the bellowji arc fully diiitt'iidcd, the cock G is to be 
turned, and the weight being {rfiuied upon the 
btdlows, the gaa is thereby passed downwardii into 
tlie barrtd, anil is there absorbed by the water, which 
is aiTelcrnted by giving the b^irrel a ft^w quick turns 
by the wioch J. The contents of the barrL-1 may 
then be ilnmn off into stone bottles, which should 
be quickly corked, and Imund down with copper 
win,:, to Iw preserved Cor use. 

A patent has beea granted to Mr. F. C. Bakewell, 
of llampstead, for a very compact and ingenious 
apparatus fur the preparation of aerated waters, the 
peculiarity of which ron.iists iu tlie gaA tcrntirnttikfi; 
and the gas impregOAting apparatus being inclosed 
in l)ut lame vnsel, and in the whole operation Wing 
cfTicted by a simple osdUating motion. A correct 
idrn o( thio machine may be formed by the annexed 
Fipirc 2, (representing a vertical section of its 
principal parts.) together with the lubjoined ex- 
planation. A A exhibit!* an external casing nf a 
cylindrical form, with spherical ends, made strung 
enOiiif;li to rrsiiit a prci^sitre of several otmnspherr* ; 
B is a (Hirtition, separating it into two parts. Thn 
bottimi part C i« a ri'ccptacLc for the chutk, or other 
•oiUble DiNtvrial. mixed into « pasty consistency 



with water ; D is a ve»*r\ containing dilutr m\ 
or aulphttric ocid, which is made to pass one bi i 
quantities, as required, at the aperture E intoi 
vessel C ; F i<t a guard to prevent the aj 
from being choked up ; G is a pipe, of tb« fa 
a truncated cone inverted, being about an indi^ 
meter at bottom, and 2 tncbea at t)ie top. 
pipe is fitted into oa aperture iu the partttioa 
is closed at the upper end : its object ii 
ascent of the gas as it is generated, which 
from the top dovm an ertemal pipe, into the 
part 1 of a vessel K, and through a small 
the tenth of on inch diameter, <or through 
apertures whose total areas do not exceed the' 
of an inch,) through the partition ioto tlw 
pnrt of the vrsAcl H. This vessel, whldt iai 
minated the washing veasel, is famished wil 
shelves, sloping in opposite diroctions near 
to detain the gis louger iu iu paasage 
aperture L to an external pipe, furnished 
perforated rose, for distributing the gas as it < 
into the water to be impregnated, contained 
vessels O O ; N is a stop-cock for drawing 
impregnated water si required ; Q is so 
for the introduotioQs of the chalk and wattf J 
another for the introduction of the acid ; snd 
opposite end of the vessel, another for the 
be aerated -. each of these apertures is provide 
« screwed cap, to stop them securely after 
spective vessels have been chat^H. The. 
is made to swing on tiro pivots. When thoj 
and acid receptacles are to be supplied iricll 
ingredients, the apparatus is to bo tuBfid 
pivots to a horiioDtal position, with tbo 
upwards, and a funnel or hopper, with • 
is to be employed in filliflg the tcsmI Ct 
whit-h is an end view of a pendulum or agit 
the form of au arc of a drde, miteodinf 
the bottom of the vessel, snd sotpeoded ati 
tremity ; the suspension wire is ahown in thai 
ing. The apparatus having been chargtd sal 
described, is to be put into vibration on its 
by which the clialk and water will be 
agitated by the motion of the pendulum, 
small portion of acid wtU eacspe from the 
into the vessel E. to keep up the generation.' 
gas as it posses off to the vinttr in A, which 
the !>Bme time, by the vibration of the appi 
thoroughly mixed with the gas as it escapes i 
the rocw. Some manufocturera of i^srated 
employ mechanical moans to force the gas ii 
water, by the use of a transferring pump on 
which is connected st one end whh s blac 
other re-servoir of the gas, and at the other, 
vrssrl, or single bottle of water; the np- 
the pump extracting the gas fnno the blade 
the down^stroke trousferriog it into the wat 
A third apparatus is even more rasfly cot 
and ecjually eflicadoui, a rcpresentatiwi of 
Figure .'t, and will he recognized as that aj 
commonly colled a soda inter maehine, and 
frequently iu sho|is wbexe this heveraga 
The lower part is, of oonrse, bidden 
counter, or it may be in a aeparatc ap&rtni 
at a considerable diritAnce. Our Fi^. 3, repr 
below three caaks furnished with funnels, 6ttiitg < 
tight and having cockft in the shank of them, 
two outer casks arc filled with spring wat«r» one ^t 
out anything added for soda water — the water inl 
other cask ia flavored with ginger and sweetened ' 
sugar fbr ginger beer, (1 ounoe of ginger 
quarter of a pound of suigar may be used 



MAC.V21NE OF SCIENCE 



179 



of Vktcr, ) Thr^r <.iuka imtb pipes in tbrm, 

litp t^loir thr »iirl'.irt^ nf the water, and 

ftbove to UiP cnck, where the Uquor is 

off. Th^ ccntrt* iru^k <.-ti!iritUi» the chalk, ami 

■iBn p«auo; from near the tup of it to near 

■Ottonk of th« sidr cavko. To charge the 

hill.- Arct fasten ali the ttibc4 that they shall bo 

turn the corka at the top off, and the 

'. 'jm the caitks on. Three quartrni fill the 

aj4j, one for soda wmCer, the other for 

r; dirn cloae tha rwpMtivc fvniieU. 

' " ! ly in the centre cask 

•1, and eloice it» fnnnvl. 

\:hi* into the sidr cask, 

rh«re, and after waiting some 

t by the cocks abfirtf. 

<ti*il^ niiii>t He mode ttron;; cnoufth 

• ■rd |»npBnirti of the g^ns, and the 

. rtfir joint. The cm Ire 

I'j t»e famifthed with a 



TDK SOLAR SPECTRUM. 

|iW|iii— lliln to trac« the path of a tiitibeam 
.i. 1^1* >rfno^4ierc without frelinf; a destro to 
, by wliAt |>»nrr it travenea the 
ptoe, nnd Ihr various modificatiODS 
At ibrt iiwiioM Mid in the interior of 
a«bst«accs. 

am pivvcd the compoqnd natvro 
•ittRtftd from the sun, by pMsini; 
HiM prism, which. sejHiniUni^ 
li . formed n »jH^:trum or obloni; 

t!' i:-<i.<itin|; of »even colors, red, 

grren, blue, indf^o. and violet ; of 
b the le«Bt rrfniTiK<'^l*^t >nd the violet 
But wht-n he r<-unit<?J these scTcn rays 
M of a Iftif, tliL' rnnipoinid beam became 
lie iiihuUtrd each colored 
r it wiia 1^ tut)^*r oapable of 

ictiiMi, cttnclitdi-d that white 
) kinds of bonm^^rticoaa li^ht. 
It*- "''dor the same refrangibility 

», ifcud u> the nirno refmngibillN the same 
Ihc diacovfrry of nbwrbent media« 
that thia U not the cojutitution 

inbiitsnne that u «ther perfectly 
or prrfcctty triitiparmt. Even gold may 
n^ chin Hi !'• Hi; i>ervioas to light. Oa 
ry, iho clojtxdt crystal, the purest air or 
ops or ahaorbit ltd r«)a when transmitted, 
lly extiugui^kra them as they penetrate 
Iter drptha. <>u thi« account, objccta canuot 
I ■( the bottom of very deep water, and many 
arc viaibit! to the naked eye frntn the topi 
than from the valleys, llie quantity 
It ta incidt^nt ou oity tran^parvnt Kubatuicu 
;r than the imn of the rcHix-tcd and 
A small quantity id irrrgnUrly rt;- 
m all diroctiona by the imperfectiona of the 
ifj whioli wfl nro irnabled to see the swtacc ; 
iMh pralcr portion i^ abaurbcd by iLu bi>dy. 
UmI n^tecl all the rayn appear white, ihoae 
tbeu Kcm black ; but uiott suhBtaocea 
dBeompoiin:! till 'thitc light which falla upon 
r>^ -4;] abtorb the rest. A 

' nlttite, and alMiorbs the 

N;irt'.; t^lAU -iliyurbi almudl all ibi: culurj 



except red. Yellow cloth reflect* the yellow ray* 
moflt abundantly, and blue cloth those thnt srr blue. 
Coiuequently color is not a property of mutter* 
but ariara from the action of matter uptin light,^] 
I'hui a white ribhon rcfle^rts all the niya, but whcai 
dyrd r<^l thr pirtlclfa of theailk acquire thr* proiM«rty 
of rettccting the red rays mtMt abandartlly iiiid otf , 
ab«jrbing the others. U|>on this property ofj^ 
ttne(|aal absorption, the colors of transparent lucdift 
depeod. For they bIm receive their color from 
thrir power of stopping or abfuirhing f<imc of tlw 
colors of white light and transmitting others. As, 
for ejiHniplc, black and red inks, though equally 
homogeneous, absorb difTerrnt kinds of rays ; and 
whcji exposed tu the sun, they become heated in 
differoDt degrrrs ; while pare water sccmt to trans- 
mit nil myi djually, and is not sensibly hrBte<1 liy 
the passin;; light of the sun. The rich dark light 
traosmicted by a smalt-Muc fingcr-glnAS is. not ^_ 
I:<jmogeneotis color, like the blue or indif;n of tl 
ffpectmra, bat is a mixture of all the colors uf «hit»- 
light, which ilw glass has not abaurht^d. The colors 
absorbed are sacb as. mucd with the blue lint, 
would form white light, When the spti-trum of 
Reven colors is viewnl through a thin phite nf this 
^lass, they are uallsd visible ; and when thn pUte 
is very thick, every color is abiwrbod between the 
extreme red and the extreme violet, the iutrrvaL 
ben^ perfectly black : but if the sjifctrum be viewcdj 
through a certain tliickne»s of thr ijlais intrrmrdiat« 
between the two, it will be found that (Ijc middle oC 
the red space, the whole of the orange, it x^'^t part 
of the green, a con.tidcrablc part of the blue, a littl 
of the indi^, and a very little of the rlolet. raniah*. 
being absorbed by the blue gU^ ; and thnt the 
ypUow rays occupy a larger space, covering t^rl of 
that fbnnef4y occupied by the orange on uue side* 
and by tlie green on the other. So that the bli 
glass obsi/rhs the red Itffht, whioh, whcu luiral' 
with tlic yellow, constitntes nrangf • and bU<» 
absorbs the blae light, which, when mixed with the 
yellow, fortus the port of the grurn spitce neit toi 
the yellow. Hence, by absorpliun, green light 
decompot^ed into yellow and blue, and orange light,-' 
into yellow and red. Consequently, the orangvj 
and green rays, though incapable of decomp««iti«w 
by refraction, can be resolved by absurpllun, and 
actually consist of two different colors iKiursiing 
the same degree of refrangibility. DllTurcnce of 
color, thercDore, is not a test of difference of re. 
frangibihty, and the coodosion detluccd by NeTt,-lon 
is no lon^vr adousBibh* as a general tnitli. By thi^i 
analysis of the spectrum, not only with blue gla«J« 
but with a variuty of colored media, fi'it David 
Brewster, so justly celebrated for his optical dis- 
coveries, has proved, that the solar speotniu oon- 
usts of thrre primary colon, red, yellow and blue* 
each of whioh txitta throughout its whole extrnt, 
bat with ditferent degrees of inteiu/ty in difTerrnt 
ports; and that the superposition of llteat* thrcu 
produces all the seven hues aocurding as each (iri* 
mary color is an CKCftM or defect. Since a crrtaia 
portion of red. yellow, anil blue rays constitute 
white light, the color of any point of the 8p#(*trum 
may be considered as consisting of the predomi* 
oating color nt thut point mlted witli white light, 
Coaseqoenlly, by absorbing thf cices^ of imy color 
at any poiut of the spectrum above what i« necea- 
sory to form white light, such white ligjht will 
appear at thit point a never mortal eye hwked 
upon before this experiment, since it possesses the 
remarkable property of rcmainlDg tba wmc aftrr 



ISO 



MAGAZINE OF SCIENCE. 



my nutnbcr of refractions, anil of being capable of 
decnrapasition b}r absorptiou alone. 

When the prism is very perfect und the sanbeam 
•mall, so that the spectrum roaj be received on a 
sheet of white paper in its utmost state of parity, 
it preaenti the appearance of ■ ribbon shadrd with 
sU the prismatic colors, hafing its breadth irre^- 
larly striped or subdivided by an indeftnite number 
of dark, and sometimea black, lines. The greater 
number of thcsD ruyless lines are so extremely 
narrow that it is impossible to see them in ordinary 
csrcum stances. The best method is to reeerve the 
apectnim on the object glass of a telescope, so aa 
to magnify them sufficiently to render them visible. 
inut experiment may also be made, bot in an im- 
perfect manner, by Tlewing a narrow slit between 
two nearly closed window-shutters through a very 
etceUcnt glass prism held dose to the eye, with its 
Tefrscting angle parallel to the line of l^bU When 
tiie spectrum is formed by the sun's mys, either 
direct or indirect— as from the sky, elouda, rainbow, 
moon, or planets — Che bUek bands are always found 
to be in the same ports of the spectrum, and under 
all ctrcumxtances to maiutaiD the same relative 
positions, breadths, and intensities. Similar dark 
lines are also seen in the light of the stars, in the 
electric light, and in the flame of combustible sub- 
Stances, thou^ differently arranged, each star and 
each flame having a system of dark lines pecolinr 
to itself, which remains the same under every 
circumstance. Dr. Wollaaton, and M. Praunhofer 
of Munich, discovered thfw lines deficient of ruya 
independently of each other. M. Fratmhofcr dis- 
covered that their number extends tu neuriy six 
hundred. There arc bn^ht lines in the solar 
tpectmm, which also maintain a li.ted position. 
Amongthe dark hues M. Pniunhofrr selected seven 
of the most remarkable, and determined their 
distances so accurately, that tbey now form standnrd 
and invariable points of reference for meminring the 
refractive powers of different media on tbe rays of 
light, wfaiiifa rrnders this dcpartmt^nt of optics as 
ciact as any uf the physical sciences. These lined 
are designhted by the letters of the nljihubet, begin- 
ning with a, which is in the red near the end of the 
spectnim ; c is farther advanced in the red ; v is 
in the orange ; ■, in the green ; r, in the blae ; 
c. in the indigo; and ii, in the violet. By means 
of these fixed points, M. Frannhufcr has ascertained 
from prismatic observation, tbe re (Tangibility of 
sereo of the principal rays in each of ten different 
■abstances solid and liquid. The refraction in- 
creased in aU from the red to tbe violet end of the 
Bprctram ; but so irregularly for each ray and in 
each medium, that no law could be discovered. Tbe 
rays that are wanting in the solar spectrum, which 
occasion the dark lines, ore possibly absorbed by 
the atmosphere «f ths su. If tbey were absorbed 
by Che earth's atmosphere, the very same rays 
would be wsnting in the spectra from the light of 
the tiled stars, whirJi is not the case ; for it has 
already been stated that the position of tbe dark 
lines is not the same in ipcctra from >tar<light and 
from (he light of the sun. The sohir rays reflected 
from the moon and planets would, most likely, be 
modified also by their atmospheres, but they are 
not; for the dark lines havo precisely the same 
pomtions in tbe spectrs, from the direct and re- 
flected light of the son. 



ILLUSTRATIONS OF BOTAN" 
(Umimtd /tkuh pagt 1(15, and 

Class XX.— GvN\NOMA. Tbn* 



I 



Staaww aailod lo the itrle. 

However tbe plants of other elaasei 
us by their fragrance, their lovely colors, 
shapes, it is in Gynandria that we most 
curiosities. ()n contemplating its gcnerm 
imagine the flowen to represent the 
ohjects. some like batter6ies, bees, 
ruus other insects, are extremely 
e>'rn resemble reptiles, and others are so 
monstrous, that the fancy is in vain 
Aimilitude ; yet there is seldom any thing 
in their appearance— on the contrary, the 
ore of great beauty. Tbey are decked in 
delicate and vifid colors — some with a (ins-; 
texture — others shining as if varnished, 
places of growth are no less varied : many i 
ornament our damp meadows and v 
them add a beauty to tbe dry chalky 
South. The Ueo flower and Fly 
recognized. But it is in the tropi 
they are seen in all tlieir splendid and 
beauty, in Bra2il, in Sumatra, and otfaeg 
regions, different of the family of Dea^ 
Onctdium, and others, hang upon tbe bi 
and climb from tree to tree, forming ever4 
garlands of surpassing magnificence and fin 
yet without earth to support then, seemh 
rive tbeir nourishment from tbe damp of 
ing air, though in truth they shoot tbeii 
Itbrous roots into the stems and branches 
tbey cling. 

Note, — The Bee flower, and other 
deous pUnts. have often been transp] 
gardens, and not flowering the next year are 
to be dead. Ibis opinion is too gensral a 
nation : it is nsii:illy two or three y 
will fully recover themselves after 
and produce flowers. This is the 
Evetlostiag Pea, and others. 

Class XXL~MoNOECiA. Eight 




\k 



SlaiTftu In crte ftoivcr. ityVi In anuth«r 

It was observed that the class Icosandria < 
almost all oar fruit trees. In the present 
lowing are placed the greater pert of 
trees. Their flowers for the most part, 
those of this climate,) are small, inaignifif 
to be found m the very early sprittg, bclbrei 
make their appearance. Tbe sUmen bearing 
are mostly in drooping catkins — the piitil 
ones near, bat diAiinct from Umn, upon 



MAGAZINE OF SCIENCE. 



181 



lUi b the case with the Nut tree, the 
iyit, the Blreh, the Bach, the Hornbeam, and 
<^Bk, bU of DatiTc growth. Porogri climei, 
bath tctnprrate and tropical, add their contribution. 
Btxmd Pmit tree, the Cocoa Nat, the Sago, the 
tY««, the Mulberry, the Chenut, and the 
•R loo Emportant lo be omitted. Thic 
~o«a not oonfino itself to trees. We 
llu vvrj nunerouB bmily of the Sedges, the 
Nettle, the beautiful Amaranthua family, 
ia, and the cahou< Arumi, to join them — 
" lait order, the Cabbage Palm, the ez< 
niUea of the Pioe trees, the Gourd and 
*'- ' Caitor Oil plant, and many othera 
■i the moit beautiful, at Least oue of 
' 1 4nd extduive arrangements. 

Clua XXn.— Dj^ciA. Thirteen orden. 



tad aitf\*» la diOarral ftowan. upOntfUSlnal plajdf. 






Prw piaati o{ Ditrcia are coltlTAted for ornament. 

iIbb in park accuery — thuii^h many for tholr 

Dwamlcal oaea. The very numcruui Willows here 

an important mnk. Some of them, with the 

trees, the Screw Pine, the Piatacbia, the 

r, dw Yew tree, and theNntmcg, arc tbe largest 

These are occonpuoicd by many 

af geiMral interest and value — the Hop, tlie 

Miailetoe, the Hemp, the Spinach, cite 

Bnlchtr'a Broom, and the Nepentbes dia- 

or Uie Pitcher phinl — one of the most 

n<tiiirc*a wotttlers. It is furaiahed with 

to the leaves, which are shaped and 

pitchers, provided with a moTeablc lid. 

B the pitcher becomes filled with water, 

nia or dew, the Ud shuts down closely 

,lAUe it U prevtmted fnim taming over by 

tochcd to Ihc. toji, at tlir back ur joint of 

tVben the pitcher becomes empty it6 lid 

lo let in a freah supply ; and in this 

kOflr a store of limpid water ia preacrTed. 

iCt grow in China, and iu the swampa of the 

and arc by no means r«re in cultitatioa 

vmatry- 




Clan XXIll, — FoLToaMtA. Two ordai. 



F)mv. perftet or luptrftct, upan th« sano or difftraut pUats, 



%^ 



V la 



Of flowering plants this class ends the summary : 
it combines Uie last two. A rather amall clasa, 
containing but one Britieh genua, and that of neither • 
beauty nor valae, the Orache. Our gardens, grt'cn- 
hooset, and houbooafls, deriTe much of their beauty 
firom the Urg« and b«MtiAil bmily of the Acacia, 
one species of which yields the Catt^u — another 
Gum Arabic. The Mimo»a family, among which 
ia the elegant Sensitive plant. The Teratrum, is 
not only uaeAil, but ornamental. The Pan Palm, 
which is the only European species of that noble 
family — while the whole concludes with the well- 
known and valuable I^ ; valuable not merely as 
fumi&hing a luscious gratifying fniit. bat one which 
aHbrda the chief food to the Grecka, Syrians, and 
inhal]itants of surrounding countries. It is one 
species of the Pig. Ficns elaadcui, which yields tlio 
Indian rubber of commerce ; and aiiotbrr of thrm 
ia the far-famed Daniao tree, sacred in Eastern «tory. 
This wonderful production is of immense migni- 
tade, stretching its branches aronnd, and throwing 
down stems, or rather roota, at intervjUs— tlicse 
increasing, support and nourish Ihe overhanging 
fufiage, tuitil at length a whole foreac ia formed frvu 
a single plaiiu 

" It was a goodly ■ifht to »m 

Tb«l verwrahl*- ic-. 
For o'er tb» lunn, Ur id. 

Fifty atiKigtit L'Vufiii' b»ihj. 

And mat>) ■■ . , Uni ibvol 

Slrniglit, Itke » plummpi, prviM UtwnriJ* Uif gtooud. 

koate on Itir lowt-r liou^lii, Mrtiirh cruit Ihctr nmy, 
FiKfou lli#!r iwkfdfd (iiirr*. rnuiid krvd r>i\iml. 
WlUi niJinx It ring luiJ Mild c<-pt<>ruan woaiwl : 
boioe to U>* {ittKUoi; wiQtl. at times, witb sway 

Of gtnUe motion in^uuc. 
Olhvra of jrnuoMir grow Ui. uimn Vil. ««r» hung 
lik« «UHW-drofM Trom (ho c-nvvm'* frvttAd bvtghL 
OfiMilb v*ii« amootli aiut r«kr to ibfkl, 
Niir wv«(l* nut brivr* dproim il t)i» nulurxt fltwr ; 
An«l lhriiut;h iht Inafy rii|ir mIiIcIi tiowirr'd It u>r 
CatiMgleofna (if obi!i)u»r'i1 l();ltL 
So llk« • Iviuplr did It »v*m, Ihiil Utrrt 
A pious brait's firsl itnpulK would Im [iraycr." 

Svctnar. 




183 



MAGAZINE OF SCIENCE. 



Clan XXIV. — Cktitogaiiia. 




<> T 



Thit clus contains all thoM plants which hare no 
ftowers. They are dtTided into the orders of Fenic, 
MosKK, HepaticR, LdL-bens, Alga: or Sea Weedii, 
and Fnngi or MusbroomH. 

Upon B review of the cluscn we find tbat the 
iD0«t ii^uL are the Srd, which prodacts our com 
and fp-aas. "Hie 12th, which furoiahes «o many of 
uur fruits, antl the 'il.tt, to which belong moat of 
our timber trees. Wc shall also find that all the 
plants of the 12th, 15th. and 19tb may be used m 
fuod witliout danger. Tlioae cIbmcj which contain 
the greatest unmbrr of plants are the 5th. 6th, 
lltth. and 19tb. llie must beantifut are the Gth. 
12th. 13th, 16tb, and 17th. The shortest cksaes 
arc the Ut. 7th. <Jth. and ISth. The most cnrions 
plnitLs, with a ft:w exception*, are found iii tJie 2Uth, 
2lBt, 2'ind, and 23rd ; aad the most mioute in the 
24 th. 



ANIMAL STRENGTH. 

Or all the first movers of machinery, the force 
derived from the strength of man or other anitnalg, 
waa first tued ; and notwitlistatxting (hr great 
power to be obtained from wnter, wind, steam, 
heated air, Ace. the strength of auimob continues 
in a roultitiide of coses not only Co be the moat 
oonrenient, bnt the only applicable source of power. 
As horsea were formerly emplgyt'd for the same 
parpoae as water-wheels, winduulla. and steam- 
mgioes now are, it baa become usual to calculate 
the eflecC of these machiueji as equivalent to so 
many horses ; and animal strength thas becomes a 
•ortof measare of mechanical force. From these 
circumstances it is desirable, that a correct estimate 
should be had of the real strength of those animals, 
employed for mechanical purposes ; but from the 
nature of sniinul organization, and from the variety 
of ci re u III stances in which the living bring mny be 
placed in the exertion of its strength, it is im- 
powible to come to any invariable standani; and 
all that is left for as to do, is therefore to collect 
together the re«ulta of many experiments, and take 
the avcmge of the whole. Wc will here present to 
oar readers, a condensed account of all that is ytt 
Ifnnwn on tliis Bubject. 

Mlien on animal is at rest, and exerts its strength 
Agoiiut any abstiiclr, tbtrii the force uf the autroul 
is greatest, nr the animal when ^tnnding still, «*iU 
support the greiUeet luud. If the aninud begins to 
move, then it cunitot support so great a load, be- 
cause a part of it» strength must be employed to 
effect the roolioii, and the grrater the itpred wllh 
whirlt the animal moves, the lrs» nill V- the fnrco 
evrrteil tm the obsUrle, or the less will be the load 
which it is able to rjirry, for the grcntrr will be the 
portion of it* stn-nsth directed to the movement of 
its own body ; and thrre will be a spred «ith wh)i.-b 
the vnimftl cait move aud carry do load, but where 



the whole of its strength la employed ia 
its velocity. It is clenr that ia the fint 
thefo cases, tbc useful elTcct of tlie 
nothing, in a mechanical point of vieir4 
must, however, be a certain relaCioa be 
load and the speed of ttie ■aimal. in ^ 
aB(*fBl effect is n majdmam. It has bei 
that the mechanical effect of any animal 
during a given time, ia greater when tlu 
moves with one-third of the greatest veloc 
which it can move unloaded, sod the load 
bears is four>iilntlu of that which it can on] 
Thus if a min can move through 7^ fc* 
second, for ten hours a day. when he ia i 
and if the weif^bt whii-h he is juat aUe to 
336 lbs., then the greatest mediamcal efei 
obtained when he move at the rate of 2^ 
second, whirh is ^ of 7|, and when he 
load of liO\ lbs., which is four-ninths of 
The nierhaoiad effect of any animal depei 
the load whieh it corrit's, and the speed wi 
it moves, conjointly ; and thus to find the 
cal effect of an nnima), we have only to 
the load by the Epeed ; hence the mechaid 
of a man carrying a load of 60 lbs.. a.tiA i 
the rate uf 3 feet in the second, is the ssa 
of a man who moves with s velocity of SI 
second, and carries a load of 90 lbs., for 
2x00=180. 

We have a few scattered hints on tlic i 
animal strength, from Smestoa. Euler. Dm 
Bod others, but it i> to the labours of Coa 
vre are jirincipally indebted ; aud the i 
portant of his results we shall therefore p 
the reader. 

If the average weight of a roan be takea ftl 
the quantity of action which he furmshe* 
up a stair will be 25IJ0 lbs., rnihcd one yar 
minute, and a man wilt with convenience 
a stair 4H(I iba., through lUUU yarda. la 
of exertion it was found that llie quantity 
of a man loaded, was to one unloaded 
two. It must be remembered, howef 
quantity of action is a very diflereut tl 
UAct'uI rtfect. When a man goca up a stair 
hi£ quantity of action is the greatest poi 
bis useful effect is nothing. M'hrn he is 
quantity of actiua is less, but his oselii] 
more than formerly. In fact, it 
Coulomb, that the gntatcst us^ul effect 
dueed when the weight wtiich the man 
0'75ti, or ) of his weight ; or aasnmiDg 
of the man to bo 150 lbs. as before, the 
be 112} lbs. 

When a man travels unloaded on a lerd 
several days, be can hardly walk more 
miles a day. which gives for the quantity < 
u:tion In this way 7700 lb&., carried 109 
The quantity of action of a man walUnig 
is to that when he walks on o level road, «« 

The strength of mt-u accordiiif; to didTcrrnft 
is very different, as the fuUowiug table will 

NsUvM or U lib Ih« hnocU. Wtll 

Van Dieman's Land 
New Zealand - - 
America - - - 
France . - - .. 
Kngluiid .... 

According to Ttobert.inn HurhnnKn, thi 
strengths of men in working a punip, in 
wineb, in riogtng a belt, and rowing a bu: 



30 


6 


31 


8 


38 


7 


09 


% 


71 


i 



MAGAZINE OF SCIENCE. 



183 



100. 167. 227, sDd 1H». AoDonStn; 
ui ordiniuy workmaii )» ftble to luc 
toob for a ahcrt tiine, with th« 
Dtt them. 

lbs. 

1^ kiufc. with a force of - - • 100 
r with two buds ..... 100 
driver, one hand ..... 84 



30 bench rire handle ... 

and awl, rertically • • . 
las handle, turtitni^ .... 
aad phc-r«, eompressing . . 
jiUne. tioriaontnily .... 
Off thumb vice .----- 45 

law 36 

bit, revolving ... - . - 16 

driveri, or twisting b; the 
or Auger* only H 

B waa formerlj much employed in the 
fl( muhiaery, and oooLinaea ttUl to be 
■ooooat it it aeoeaaarr to direct our 
re of the average force of thia 
■treogth of the horie there ii aboat 
of opinion, u that of man* 
Snicaton atale the strength of a 
Talent to five men ; whcrL-as the 
it seven. Probably the truth 
be t ween the two, and we may with 
Mtimate the strength of a horvfl to be 
k, at a dead pull. It is however to be 
compttnngthe strength of a liorso with 
, thai the most advautageoas way to 
Crength of the one, ii the least ad- 
other. The worst way to apply 
horse, is to make him carry a 
hill, while the structure of a man 
well for that purpose ; wherefore tlirec 
bcftrieg a load uf 100 Iba., will procet^ 
hill, than a horse with 300 tbs. 

of applying the weight of a horse, 
draw a loaded carriage. A horse 
and endesTOuring to draw, bends 
and inclines his k^, bringing his 
earth, and thiA he nill do the 
the effort he uiukeii- In thia way 
that the effect will dejicnd in some 
his own weight, and also upon the 
on bis back. It is therefore useful 
beek of a horse when in draught, 
tint sight it might appear a hindrance ; 
skilful nf tbofie who mansge draught 
aware of this fact, adjust tlie load 
) cart^ or carriage, sa that the shafts 
n of the weight upon the horse's back, 
1 operate* with the weight of the 
dimioibbing the exertion of strength 
for draught, which marc than compeoiiHtes 
Irden on the back. The best disposition 
a while the horxe i^ drawing, is to be 
to the plane of the collar upon his 
1 shoulders. When the horse is standing 
position of the traces is rather inclined 
from the direction of the road, hut when 
leans forward to draw the load, the traces 
k nearly parallel to the road. If the horse 
in drawing a sledge or any other thing 
rbeeU, the inclination of the traces to the 
vary with the proportion of the friction 
with the pressure. Thos if the friction 
rd of the preasure, the inclination of the 
the road, will be according to a table, (see 



way 



Gregory's Math. p. 241.) iH^'\ and the same table 
will give the angle for other proportions of friction 
to press lire. 

When a hone is employed in a gtn, as is of^en 
practised in grimling and thntshiug mills, it is 
desirable to give as great a diameter as nonibtc to 
the circle in which the animal walks. It is clear 
that Hince a reciirmcsr motion ti easiest for the 
horse, and that with the same velocity the centrifu- 
gal force will be less in a large circle, than in a 
small, which will proportionately lessen the friction 
in the trunnioos, that it Is advantageoua to have the 
diameter of the gin circle huge. 

In practice, it may be stated, that the diameter 
of the gin walk ought not to be leas than 26 or 30 
feet. 

Mr. Tredgold gives the following view of a horsc^s 
daily labooTi and maximum velocity unloaded. 

DlT«ctlon of UtKiiir Uaxlnium ▼•loclty In mths 

pvr boor onloraed. 

14-7 

10-4 
d-i 
7-3 
6*6 
6*0 
ft-5 
5-2 
4-9 
46 

l^iking the houn of labour at 6 per day ; the 
same author assigns 125 lbs. as the maTimum of 
useful effect, moving at the rate of .1 miles an hour ; 
and regarding the expense of carriage in that casd 
OS I, he gives : 



Milea pfr bour 
2 
3 

34 
4 

5 



Proportloml «Kp«i»r 
1-125 
1 

V02S2 
1125 
1-333 
1-8 



Movttif rorea. 
IGG 

ie& 

104 

83 
62-5 
41-G6 
5fi-5 



Mr. Trcdgohl states, that a horse working; 6 hours, 
will raise 2'ijO lbs. one mile. Mr. Bevau makes 
the number 20HO. 

According to Desagullers, a horse's power is eqiu. 
valent to 440UO lbs. miFcd one foot httrh in one 
minute of time, Smeaton makes the number 229 Iti ; 
Hachette, 28000 ; and Watt. SliOOO. 



LIME IN AGRICULTURE. 

QcicxLiiiB, In Its pure atate, whether in powder, 
or dissolved in water, is injurious to plants, nrass 
is killed by watering it with lime-water. But lime, 
in its state of combination with carbonic arid, is a 
useful ingredient in soils. When Itme, whether 
freshly burned or slacked, is mixed with any moist, 
Hbrona, vegetable matter, there is a rtrong action 
between the lime and the vegetable matter, and they 
form a kind of compost together, of which a port is 
usually soluble in water. By this means, matter 
which was before comparatively inert, becomes nu- 
tritive ; and, as charcoal and oxygen abound in all 
vegetable matters, the lime becomes converted into 
a carbonate. Mild lime, powdered limestone, marlsi 
or chalks, have no action of this kind upon vege* 



\M 



MAGAZINE OF SCIENCE. 



Xab\ii matter; by their sctinn they prevent the too 
rapid dfcomposition of sutMtaaces already fUswIred, 
bat th?y have uo tcudmcry to form soluble matter. 
Prom ibnc circumstance it is ob^Honii, that the 
opcn&tioD of quicklime and mnrl, or ch&lk, dppcnds 
upon principici altogether dilTercnt. Qmcklime. in 
the ai^t nT becoming mild, preparer toluble out of 
iiMolublr matter. It in upon this circumstance that 
the oprratinn of lime, in the preparation of wheat 
cropn drjirtulii, bdJ its efficacy in frrtilizing peata, 
imtl in brining: into a state of cnltiTstion all »oUa 
abounding lu hard routti, or dry fibres, or inert tv- 
getable matter. The solution of the question, wbc- 
tiler (juicklime ought to be applied to a aoiI, dc- 
prndx upon the quantity of inert Tegctablc matter it 
contAins. — The solution of the question, whether 
mar), mild lime, or powdend limestone, ought to be 
applied, depcndi upon the quantity of calcareous 
matter already in the »oU. All soils are improved 
by mild Jime, and, uUimat<-ly, by qnickltme, which 
do not efrrrveact! with acids ; and sands are more 
benefitted by it Ihan clays. Whrji a soil, deficient 
in calcareons matter, contains much soluble, vege- 
taUe manure, the ippliL^ati'm of i)U)cl:lime should 
nlwayi be avoided, as it rtthrr tends to decompose 
tbe aoluble matters by anitini^ to their curbou and 
oxygen, lo as to become mild lime, or it combines 
with the soluble matter*, and fnruia compounds 
bsrinjT less attraction fnr water (ban tbc pure vege- 
table mbstancc. The caite i« the aime with respect 
(o most animd manures; but the operation of the 
linae is difTereut in ditftrrent cases, and depends upon 
the DDtnre of the animal matter. Lime forma a 
kind o( in«olable soap with oily mntters, and then 
f^adually dccom|ir>!ipi* them by sepnratinp from them 
oxygen and carbon. It combiner, likewiite, uith the 
Xnimal scid^i. and probably (isj-ists iht-ir decomposi- 
lion by ■batmitin|L; cnrbonnceous matter from them, 
•inmbine*! with nxy»rn ; ami, ronsequrntly, it must 
render them \csi nntritivc. It tends to diminish, 
likewise, the nutritive powers of albumen, from the 
anme causes, and always destroys, to ■ certain ex- 
lent, the efficacy of animal m.-inarea, either by com- 
bining with crrlaiii of tbrir cirments, or by giving 
to them new arrnnircnienta. Lime should never be 
applied with nnirmU manures, unless tlu'y are too 
nob, or for the purpose of preventing noxious 
effluvia. Il Is injurioui when mixed with any com- 
mon dung, tending to render the extractive matter 
jusoluble. In those c«ars in which fermentation is 
usefiU to produce uutrinteot From vegetable sub- 
■taaoei* lime is always eUicadgus, as with tanners* 
btrk. 



7b /*e Editor. 

8in— If you could oblige me by tbe msertion of the 
f^rflowiag origlnid article in your very valuable 
journal, you would much oblige a coiuUnt reader. 



THEORY OF THE PRODUCTION OF 
METEOROUTES, OR METEORIC STONES. 

The proposed theory ia founded upon the follow- 
ing (acts, viz. 

1. Meteorolites are entirely composed of iron, 
niekel, and aometiines ■ small proportion of cobalt. 

2. The three above mentioned metals arc the 
<kily three lusceptible of magnetism. 



3. Their descent kia alwtya beta 
by electric pbenomeu. 

4. Wherever thpre ia an elcctnc rnrreni 
always a current of magnetism at right an( 

5. Iron the moat abandaot formi tfa 
proportion of their balk. 

A. They arc never found except in 
nickel is found. 

Is it not very probable that the eff 
powerful magnetic currents (set in aclita 
electric currents at or before the time of i 
scent) may attract the above named oietilt 
earth, and at the annihilation of the oppa 
tricitiea the magnetic currents being de^ 
metals nnattracted or unretaiikcd by any 4 
through the atmosphere, become attraotivs 
other, funn raassea, wbicU from the beat 
by their rapid descent are fused, and 
agnin to the earth ? 

Profcs»or Urande's Lunar Theory fe^mt 
very improbable, when we consider thu 
inruls above mentioned onfy arc found 
into their rompositton; — on account of 
depth to w4i{ch they penetrate into the eart| 
descent, the force not being so great as 9 
ought to have acqoired in travelling from 
to our earth ; also it appears very itnpro] 
any force, hntrever conci-ntrated, eoold im] 
of their usual small aize from tbo 



the extent of «tirface presented fur the a] 
of any force seems fnxaflBdent; and 1/ I 
from a volcano in the moon, would yoa t 
traces of sulphur ? 



MISCEU-.VNIES. 

Anxirer to Query ISA. — Tlie materiali f^ 
printing inks are as under; — 

Rtd — Mineral orange rod, 2 oz. ; Chii 

los. 

lihe — Celestia] blue, 2 ob. ; mazaripe td 
Green — Mineral green, }ox. ; chrome g1 
/Jroirn— Burnt umber, i ox. ; roee pifl 

English Vermillion, 2 drams. 

I^lae — Prussian blue, ^ot. ; Indian red 
Lilae Pynk — Mineral pink, 2 ox. ; satin 

French chalk. 3 ox. 

Orongt — Mineral orange, 1 ox. ; cfaron 

2 ox. 

0/«e*— French blaclt, 4 A. ; lamp blad 

rock indigo, 2 oz. ; Indian red, 2 ox. 

The above colors to be ground in print 
oifih. 

Ej-tirpclinff WtfdM, — Weeds may be 
from ^^un in|; on gravel walks by watering 
with salt and water. The salt will uto 
weedR alreedy there ; and if these art 
should, of conrse. be hoed up and i 
SMerbeme Mcrctuy. 

Fluid for Wriiinff on Knife-bladei, 
Pound and mix together intimately ^ox. 
\ oz. alum, and \ ox. riaU ; (Ken put in a 
of best vinegar: afler ttamling two or 
take yellow Kwp and spread it thinly oDdj 
on the urtick to be marked, and write wit 
mon qUill pen. 



JMrMVM.—Friattil by P. FaAircii. (. While Horse Uii*.U\\««.iiA.—V^>iVub«ft^>jW. B«mM>. Il.riii 



THE 



AGAZINE OF SCIENCE, 

StiiO Retool of ^xtg. 



.] 



HEW EDITION. 



[Urf. 



Fiff, J 




xxtv. 



186 



MAGAZINE OF SCIENCE. 



ATMOSPHERIC RAILWAYS. 

Pntitmaiie Trmiport. — In the yetr 1824, the 
fngcoioiu Mr. John VallADce, of Brighton, took 
out ft patent for ft mode of employing the attnral 
pressure of the atmoftphere, operacing upon a partial 
Tacnum, for the purpose of transporting persona 
tod goods with extraordinary rapidity from place to 
plftce. He proposed to constrnct hollow rylinders 
of cast-iron, fufficientlj large to allow carriages with 
paaaengers and goods to pass throuj^h thrm. A seriea 
of Iheae cylinders were to be uuitrd. and extend 
from town to town, and the junctiona made suffi- 
ciently air.tight to admit of a rarcfartion of the air 
within the tube, by the continued action of power- 
ful exhausting machinery at one end. The carnages, 
which Kere to tntvel inside of this tube, were to be 
of the B.imc cylindrical form, and very nearly of the 
same tniusTersc dimensions, so as to constitute, in 
eflfcct, pistons, which wiire to be itnpclled by the air 
rushing in at one end of the trunk, to restore the 
equilibrium, or fill up the vaonous space mechaai- 
Cftlly produced on the opposite side of the pistons. 
A model, on a sufficiently large scale to test the 
efficacy of the jirinciple and mode of action, was 
Bet up on the patentce'i* prexnises at Brighton, and 
many^ persons were thus b/tnen through the tube. 
Notwithstanding this demonstration of the correct- 
lieu of the principle, sufficient subscriptions were 
BOC obtained to carry the plan into effect on a greater 
scale. A notion was rery generally r-ntertained that 
the scheme, if feasible, could not be carried Into 
inctice on an extensive scale, and at a cost that 
voald repay the subscribers ; to this circumstance 
B&ay also be added, a fear that the extraordinary 
mode proposed, of travelling in the interior of a 
tube, would not accord with the taste of the public 
The latter objection was, however, obviated by a 
Dorel arrangement of mechaniiim, which became 
the subject of a patent granted to Mr. II. Pinkus, 
whose invention consists in transferring the action 
produced upon a pi<rtoD or dinphragni, moving in 
the interior of a tunnel or hihe, lo its exterior, by 
connecting a vehicle or machine, situated within the 
tube, with a car or carriage without, tu which the 
train of transport carriage* are attached. A work- 
ing model of this invention was first exhibited in 
Wigmorc-strect, CsTendish-squnre; and thus this 
aingular mode of transport gained considerable 
celebrity, the princtplt! upon which it is founded 
being ensenlially correct. 

Mr. Ptnkos's arrangetnents were loaded somewhit 
with unnecessary machinery, and the continuous 
nlve was not sufficiently perfect to ensure certain 
success — though as the first Application of a new 
principle it deserves the greatest praise, and his 
more fortunste successors, Messrs. Clegg and 
Samuda. are indebted to him for every thing except 
the minor details of the valves, rendering them safer 
and more easily worked. In this improved condition 
it is that the atmospheric rail-road is now engaging 
the public attention. To explain its general princi- 
ples and construction, we give two extracts, one 
from the " EnKincer's Encyclopedia," — the other 
from a ** Pamphlet published by Messrs. Clcgg and 
Samuda," and to which latter we beg to refer oar 
' readers to estimated profits, expenses, advantages, 
* ftc., of the undertaking. It may be had at Wcole'a 
ArchitiKtural Library, Holbom. price Is. 

** He pneumatic railway admits of arveml me- 
thods of application, in each of which the dimeo- 
AoM, economy, and details, vary. On a line of 






roftd where the transit is very great, aa, for exaa 
between Liverpool and Manchester, a double 
would be required, the eylinden of which, A* 
patentee states, shonld be 36 Inches in diazoelVp: 
and so moulded, as to be of the ftverage thickoni 
of three -quarter! of an inch ; that is, the lowtf 
6emi>circnmfereace to be three-quarters of an iochi 
and enlarged into a series of rings three feet apart; 
so as to be H inch thick where the rings occur; 
thus giriog the lower semi-circumferenoe an areragt 
thickness of seven-eighths of on inch. The nppc. 
«emi.cireumference need not be of a greater aicrafl 
thickness than five-eighths of an inch, when disposei 
into similar rings. On a single line of road, whsrr 
the transit is considerable, the size of the cytladm 
may be increased to 40 inches diameter, and be Ot 
a proportionate thickness ; but when the pneumaCK 
system is combined with a common rail-road, tliatis, 
laid between the ordinary rails, aa a medinm for 
transmitting motive power to carriages runniug la 
the usual manner on rails fixed upon blocks, the 
cylinder not having to sustain tbe weight or aottM 
of tbe loaded carriages, may be reduced to 28 inabw 
diameter, and half an inch thick : and when Aft 
system is applied to draw or propel barges on cai)ftl% 
(which is also contemplstcd by the patentee.) 4 
cylinder of only 22 inches diameter. Uid dowa bi 
the towing-path, he considers to be folly adeqsotlt 
The length of the pneumatic tube will be equal ta 
the whole length of tbe railway or canal to whidli 
it may be applied, and it shonld be east in portiflM 
of the greatest length possible, in smooth nald 
moulds, sothot their inner sides should be verycrM 
and true, and they ore to be connected by the ordi- 
nary socket joint. 

" Figure 1 , is a general elevation of the rulw^i 
with A train of carriftgea passing over it. 

" Figure 2, is a plan of the railway, with thi 
upper surface of the pipe, at the part oontainia| 
the entrance separating valve, removed, to show iO 
coostniction. 

** Figure 3, Is a longitodina] leciioa of tbe ndl< 
way, showing the coBneotion between the piston ni{ 
the trnin carriage, and the method of Ufking dri 
continuous vmItc. 

** The moving power is communicated ta th| 
trein through a continuous pipe or main. A, UU 
between the rails, which is exhausted by air pam|i 
worked by stationary engines, fixed on the road 
aide, the distance between them varying from onet) 
three miles, according to the nature and traffic 
the road. A pistoo, B, which is introduced ialj 
this pipe, is attached to the leading carriage in M^ 
train, through a lateral opening, and ia made tt 
travel forward by means of the exhaustion in 6tHl 
of it. The continuous pipe is fixed between tfal 
rails, and bolted to the sleepers which carry thevi 
the inside of the tube is nnbored. hut lined or oeoM 
with tallow one-tenth of an inch thick, to equalli 
the surface, and prevent any unnecessary frictMl 
from tbe passage of the travelling pi&ton thro«|jl 
it. Along the upper surface of die pipe is • enm 
tinuoDs alit or groove, about two inches wide. Thi 
groove is covered by a valve extending the whdl 
length of the railway, formed of a strip of h^fhm 
rivetted between iron pktes, the top platen bdfll 
wider than tlie groove, and serving to pie*ssit fli 
external air forcing the leather into the pipe whM 
tbe vacuum is formed within it ; and the lowe 
plates fitting into the groove when tbe valve ia stud 
makes up the circle of the pipe, and prevents Ihl 
air from pasting the piston; one edge of tU 



MAGAZINE OF SCIENCE. 



197 



irely held down hj iron ban, ttf a loa)(i- 
out on the pipe, «nd allows the leathor 
Ihe platca and the bar Co act u a Kiage, 
a oommon pomp vatre ; th« other edge of 
lUU into A groove which cODtaios a com- 
beea'*wax and tallow : thii composition 
the temperature of the atmosphere, and 
fluid when heated a few decrees above it. 
Talve i% a protcctiog cover, which serves 
it from snow or rain, formed of thia 
ran, about live fftt long, hinged with 
asd the ead of each plate underlapa the 
the direction of the piston's motion, thus 
■tBf Ike liihog of each in anoowaion. To the 
laida of the firat carriage in aaok tnin is at- 
•A Iht piaton, B, and its apportenanoea ; a rod 
Bg horiaoalally firom the piston is attached to 
Utectini; arm, C. about six feet l>eltttid the 
a. Thia connectiag arm paasci; through the 
groove in Uie pipe, and being fixed to 
, imparta motion to the train as the tube 
Hi efthaosted ; to the piston rod are also 
M four steel wheels, H H, (two io advance 
wo behind Che connecting arm,) which serve to 
le valve, and form a space for the passage of 
MDarting arm, and also for the admission of 
&• baek of the piston ; another steel wheel 
lafi^tti to the carriage, regulated by a sprinj^, 
I aerTet to ensure the perfect closing of tbe 
I by rvotiing over the top plates immediately 
MMann has passed. A copper tube or heatrr, 
lOQl ten feet long, constantly kept hot by a 
itove, Z, also fljced to the under tiide of tbr 
fe. paises over and melts the surface of 
iMilioo (which has been broken by lifUng the 
) wliicii upon cooling becomes Aolid. and 
iJl Uy seals the valves. Thus each tmin in 
^Dnrca the pipe in a fit state to receive the 

^m corotuinona pipe is divided into suitable 
^{according to the respective distance of the 
■Icua cngioes) by separating valves P and Q, 

aiv opened by the train as it goes along : 
vsUea are so constntcted, that no stoppage or 
ulion of speed ii necessary in passing from 
KSioo to another. The exit separating valve 

tkaC at the end of the section nearest to i(« 
> engine, is opened by the compression of air 
■t oT the p' ^n, which necessarily takes place 
It has passed the branch which commaoicatPA 
Ifce air-pump ; the entrance separatiDg valve F 
near tiic commeDcrmrnt of the next section 
^) ia an equilibrium or balance valve, and 
I immediately the piston has entered the pipe. 
tamn pipe is pat together with deep soclEet 
, in each of which an annular space ia left 

the middle of the packing, and filled with a 
■aid : thus any possible leakage of air into 
be b prevented. 

rhe following accounts of the working of this 
n on the fi^nninghsm, Bristol, snd Thames 
Sod Bailroad. will prove its efficiency. 
fhe part of the line on which the system Is laid 

is between tiie Great Western Railway and 
[yWd^ line, on an incline rising part 1 in 



HdptrC 1 in 115. 
Am section of vac 



vacuum pipe is half a mite long, 
internal diameter. 
[In exhausting pump is 37^ inches diameter, 
2| inches stroke, worked by an engine of six- 
rvr. 

of experimenl. s series of 




posts were fixed along the half mile, erery two 
chains spart, and s guage at esch bod of the pipe, 
for the purpose of ascertaining the degree to which 
the pipe was exhausted. A vacuum equal to • 
colomn of mercury of IB inches was obtained in 
one and a half or two minutes, and both gnsges 
indicated the aamc extent of vacuum at the 
iofltant." 



COLLECTING SHELLS. 

Iiv coUectinf abeUe the implements required arc few 
in namber. The principal of these is s Isdle or 
spoon, msde of tin or thin iron, 5 inches long and 
3^ wide, with a rim about an inch in height; it may 
have a short hollow handle, by which it may be 
fixed to the end of s long walking stick ; the middle 
should be perforated with holes, no larger than is 
sufficient for the paasage of water. This tnatni- 
ment is very useful in fishing for small river sbcUs, 
or for sifting fine sand on the sca-sbore. One or 
two strong knives will be necessary for separating 
limpets, ear-ahells, &c. firom the rocks. A ham mar 
and chisel, for procuring such as perforate ; and 
small tin boxes and bogs for containing the speci-^ 
mem. In searching for the larger frcsh'water bi- 
valves, a landing net, with very small meshes, tt ot 
great service, and it may be made to fit upon the 
same stick as that which receives the ipooa already 
described. 

Msrioe shells are the most numerous, and there 
are few situations on the sea^coasts which do not 
produce some species. The luwest ebb of the tide 
is the best time for Kesrrhing for them. The rocks, 
corals, and stones, which nre then left exposed, 
should be carefully examined for chitons, limpets* 
ear-shells, and other adhesive tribes, which are 
fixed npon the surface, or shelter themselves in the 
crevices. They are detached by suddenly passing a 
knife between them and the substance they are 
upon. Muscles, and other gregarious bivalves, 
furnished wirh a byssus, likewise occur in such sitn- 
ationa. \Miercver the rock, mud, or ssnd, is pierced 
with round holes, the collectur may be tolerably 
sure of finding bivalves: they are procured either 
by breakini^ the rock with a hammer, or diE;^iug 
deep into the sand or mud with a spade. The bttle 
puddles of salt water, left by the tide, are the hobi- 
talions of many univalve shell* ; and others will be 
found beneath loose stones and sea-wetuls. If any 
shtlU appear to have been recently cost up on the 
beach, and are not broken, they may be collected ; 
bat such as have lain some lime, exposed to the 
friction of the wares and the best of the sun, ar« 
scarcely worth that trouble. After a gale of'wind, 
or violent storm, the shore should be immediately 
visited, as fine shells sre frequently to be met with *. 
if the line of coast is eiteniive, a few boys should 
be cngiiged to assist in the search. This must be 
dune quickly; for it not unfrequently happens, that 
the next flow of the lide takes away every shell. 
Small islands and coral reefs, not exposed to violent 
aurffi, are generally very nob in shells, particnlarly 
in did^erenC species of Spottd^tiu, trea-oysterft 
(Dfndmttrr*), cUms (Tridacna), winged mwclat 
(Margarita) , and other adhesive or byaaifbroos bi- 
ralves. 

The /rwipr, or dragging net, upon a prvdnrtivo 
coast, will generally briiig ap a variety of living. 



\w 



MAGAZINE OF SCIENCE. 



■ 



18 wdl u of oUicr 11111110 inlmiili 
Wfanww dead or brokea ihells arc drmra up with 

the soanding line, or obaerred apon the beufa, they 
afford tax ilmost certun indication of the oomft being 
productive. Tlie trawl should be tried in every 
dircctJoD, both ui deep and shallow water ; und 
whsa oace the ahelly ^rouod baa been discovered, 
the collector may calculate upon procuring a vwieky 
of Bpedcfl peculiar to Bucb waters. Shell-ttsh of a 
carnivorous nature may be caught in lobster pots, 
which they frequent for the purpose of feeding u|Hm 
the ofTal used as baits. In the Mauritian i^lnnds it 
IB a common practice to Ash for olive and harp 
•hflUa with a Une and hook baited with fleah : this 
mathod, no doubt, might be employed with great 
advantage on other productive ihores. The Ash 
markets in Catholic countrica should he r^ularly 
Ttaitod, partimlarly during the season of Lent, when 
shell-Ash constitute an important article of food to 
the inhabitAnta. In the market of Naples, are 
oltott MCD fino •paoimens of Cardium irpmomm and 
MBlsateM, FtcUmcuhu pilonu, Ftctm Jaccb^, 
and Mri«f Mwrtx brmidama, and many other 
species of a emaller sise, thus exposed for sale, 
merely for the Bake of the fish. Trawling in the 
bay would produce, without doubt, a still greater 
number. At Tanmto, at:cording to Swinburne and 
Ulynea, the variety and abundance of shell-fish ia 
prodigious : the latter author enumerates 185 
•pedes, found by bimsetf at Taranto and Naples. 
^ells, also, are procured by divers or pearl fii^hers 
in various porta of India. It baa been laid that the 
magniflcent collection of shells formed by the late 
Mr. Griffitlis In the island of Snmstra, were nearly 
all procured in this manner. The sea, in the shel- 
tered bays and coTes of tropical climates, is at times 
a* clear and trnnspnrrnt, thnt objects are distin- 
girithed at the depth of fifteen or twenty feet. The 
eoUeotor should avail himself of this, by usiDg a 
small hand-net fastened to a pole, by which the 
bottom may be scraped. 

The most productive coasts for shells are those 
of the continent and islands of the Indian Ocean, 
from whence near one-fourth of the exotic species 
unalty seen in cabioeta are brought. It may be 
takvn as a general rule, that the shores of islands 
abound with more shells than those of continents. 
Ceylon, Amboyna, Sumatra, and Java, ha*e long 
beoi celebrated for their shells ; bnt those from 
Borneo and New Guinea are very little known. The 
island of Timor may be called the paradise of con- 
chologists ; for it has frequently been averred, that 
no part of the world can be compared with it in the 
variety and profusion of its marine productions. 
The coasts of Australia are considered productive, 
yet not particularly so. From the PaciAc Inlands 
many beautiful and rare speoies have been obtained ; 
and numerous others, in all probability, remain to 
be discovered. It ia singular, that while the eastern 
OHSCa of South America are particularly barren, the 
sreatem shores are found to be plentifully inhabited 
by testaoeOQS animals, more especially those of the 
eyclobniochian tribe, or chitons, numerous apedes 
of which, of late yean, have been reoahred Arom 
Chili. In Britain, the weat of England aflbrds 
nearly two-thirds of all the marine species yet dis- 
eovored. ^be coast of Ezmouth, Sandwich, and 
Weymouth, are particularly prodoetive ; S(f likewise 
ar« those of Tenby, Barmouth. Hastings, &e. In 
Ireland, Dr. Tnrton has explored Bantry Bay, and 
the celebrated silver strand of Portmomock, in 
Dublin Bay, with great ssaidmty and lingular 




sai,— ; while ia Scotland, a eonaidenUv 
of rare md interrsttng shells have betsfc d| 
in the Frith of Forth, by Captain 
acenrately described by him in the 
tMe H'trmfria» Saeifty. 

Fiiwiatile $hrlt* may be loaght for bi 
lakes, ponds, nvers, streams, and ditchc* 
brookn. The greatest number of the 
ooenr at or near tiw surface, Hadcr<tbe 
aquatic plants, among decayed vrgetables 
bWahres, on the other band, as also th« 
Mtlattite, Paikdhup, among the unhralvea, 
to l>e found at the bottom, either among the ft 
or partly imbedded in the sand or mud 
arc easi^ captured by the hand, or by 
already desenl>ed ; but the diflerrnt species 
(•'nio, AneHon, Stc, from fixing themsclv 
the mud (vrry often two or three inches 
surface), can only be extracted by a s 
circnlnr landing rtet. somewhat resembling 
miniatnre — the curved portion being 
the handle if Httacbed, while tke st 
front : this side, which comes in 
bottom, might be furnished with three or ' 
prongs, like a rake, which would detach I 
from tha mud ; while the net, being drawn 
would receive them. Many of the E\mi 
tile bivalves are minute, and can only be 
a net with very small oieshes. There a 
any iituatioiu in this country where frq 
shells rosy not be found. The exotic 
particularly engage the attention of the 
The great rivers and l.ikea of North Aaaerii 
with a surprising number of these Invalv 
of which grow to a very Urge siae and ai 
thickness. Although we are now weU a 
vrith those of North .\merica, lew, coffif 
have yet been brought firom Che tropical 
that continent, — sliU fewer from Asia, am 
any Avm Africa. As no caase haa beaa aa 
such a singular ditRparity. we maypreMiin 
casioned by the fresh waters of thoae ra 
having been sufficiently examined. 

Land tkelU occur in all cfMiotriea. and 
in various situatitins; ss humid apota core 
herbage, rank grass. Stc. ; beneath tike bl 
within the hollows of old trees, orevfoea of 
wails, bones. Ate. Early in the morning, 4 
damp sunless day, or after ahowen of rail 
mollusks may be found crawling on the le 
plants, the stems of trrr5, flee. The 
sometimes live in a torpid stale for one or 
after they hsve btrn removed from t 
country : it is therefore highly desirable 
experiment should be tried with a 
s[>ecles; packing them in moss, or louaa vv 
earth, but in such a way that they may not be 
during the voyage. J 

The animals of all shells may be hilled ill 
water, in whleh they (ihould remain two 3 
boars. The water n^st not boil, oiberw 
colors, in many cases, will be changed 
Previoui to removing the aninml, the si 
be simply eletined with water and a h: 
Spirits of silt, or other acids, on no acco 
be used : they are, indeed, employed 
scurf, or any extraneous bodies that some 
the besnty uf the specimens ; but their 
requires much skill, and will prove des 
the hands of incxpcrianoed pereons. 
shells, therefore, have been cleaned wit^ 
the dead animals can be removed wiOi • 



MAGAZINE OF SCIENCE. 



1S9 



It of ft ki^fe : the laftter will be ncctaauj 
the twt> niG»ctrf, gcnermUy found la bi- 
br which the vaWea are rloaed. The 
tbcw »bellA sre nerer dead antU these 
and the taItcs ticgin to gape. 
I, great ctre must be taken not 
1 md it ii denrablc that the li^- 
ib«uld be prrscnrrd entire. TheopeTCQlnm, or 
kfaih cloaca the month of nniralTea, should be 
BtAta ih ^» wrapped in paper, and replaced 
HklMrtnrei. The ahetls mar be left to drain 
^■M#aod board placed in the shade. In 
^^^Blriee, tlie mniatwicf) of anta majr be 
^Mb advantage. 

' ay ahellt, the fmaller and more delicate 
be beat aeeuivd from iojury in chip 
to tfaeac ibould be affixed labels, ataliog Ibe 
J were foond in, and any other circum- 
Hioec armed with long and tender epines 
r be enveloped in cotton or tow, vntil their 
• aonfteieljr covered: the rest may be 
JlkMlllllit paper, or other soft substance, 
taking care to put the largest 
at the bottom, sod filling op the in- 
with the smiiUer species. Many of these 
», may be packed, with greater security, 
te large oucit ; thus the rixk of lajury will 
■nd modi space laved. 




CHEMICAL TESTS. 
(JUnmed/rompa^ 168.^ 
pJ^VH m mnernf Wgtert. — To any rni- 
r, ttt^pCcted of coataining iron, add a little 
precipitate of carbonote of lime, 
ion of oxide of iron, which is of a 
color, will fall down. Pour a few 
solutioD of succinate of ammoDia into 
containing any flnid where iron is Bua- 
to exist ; for example, a solution of the ma- 
if iron : there will instantly be a c«pioui pre* 
Ce of succinate of iron, whilst muriate of am- 
i will be held in solution. Chalybeate waters 
iroved to have iron in solution. 

m Solution. — Pour about ten or 
of nJtro*munate of gold into a wine 
ig diftiUcd water ; the mixture will in 
be colnrlcrt, but if it be stirred 
a piece of tra, or a slip of tinned iron, 
le the appearance of port wine. This 
lich is the same as that known by thr 
jmrple preeipitate of Cattiu$,) will 
in the form of a purple powder. 
Ptatiirvm and Jhr Potast. — Poor some 
ion of carbooate of potasa into a wine 
Ining some diluted nttro-mnriate of pla- 
yellow precipiiarc will fidl down. As a 
of soda ha» not this efTwt, s very ready 
li»co*rrin^ the existence of potass in com- 
is by letting full a firw drops of the nitro- 
.into the suspected solution. 
)r frftn and Copper in Alum. — Sulphate of 
md poUn very often containa sulphates of 
hmI coppf r. These may be detected aa follows : 
drams of the alum in hot water, and 
ion into different wine glaases, into 
poor a few drops of a solution of pnu- 
potass ; if iron be present, a dark blue pre- 
ivtU take place ; this is the prossiatc of iron, 
Uoe. Into the other glass poar a solU' 



[wht 



don of pore ammonia: if copper be present, a 
beautiful light bloe color will pervade the liquid, 
from the precipitation of ammoniuret of copper. 

Tetti/or Teltttrium. — In a aolution supposed to 
contain telluriom. Immerse a tin rod. If tellurium 
be present, it will be precipitated on the rod in the 
metallic state, it will have a greyish white lustre 
similar to the tin itself. To prove beyond doubt the 
existence of the tellurium in the dulution, tlte pre- 
cipitated metal should be wiped oO from Uie rod by, 
B feather on a piece of paper. A further test for 
the presence of this metal, ifl a small quantity of tho 
Eubcarbonate of potass, which will throw down a 
white precipitate. Eiperiments should be made 
with both these on different portions of the liould 
to be tested. 

7>*r» /or Lead and Copper in Wtne, ^'c. — Put 
into a crucible one ounce of sulphur, and one oaace 
of pure lime, and keep them in a while heat for 
nearly half nn hour; when cold, add one ounce of 
the 90 per -tart rate of potass, and boil the whole in 
a mattress with some dietillrd water for about half 
an hour. Dn:ant the supcrnalant liquor into small 
phials, adding about twenty or thirty drops of mu- 
riatic add to enrh. The phiols moat be well stopped 
and preserved for use. Lead, copper and olher 
deleterious mctaU wiU be precipitated, of a black 
color, by this liquid, if poured, in the quantity of 
only a few drops, into the suspected wine or cyder. 
The muriatic acid is added to this test, to prcTcat 
the prrcipitatioD of iron, which might exist in the 
wine without any mischief resulting from ita use. 

Another test for these pernicious metals in wine 
find cyder, exists ready formed iu nature. Pour 
into a glass of suspected wine, cyder, or perry, a few 
drops of Harrowgate water. If any lead. &c.. b« 
present, it will fall down in the state of a black 
precipitate, being combined with the sulphnrctted 
hydrogen by which these waters are impr^natodi 

C7b be emtiimud.) 



THE CHARCOAL GALVANIC BATTERY. 
IT UR. svsa. 
Ma. Suit Rsys. that *' 1!Mien a diamond is placed 
incontact witn amalgamated zinc in dilute sulphnric 
sdd. no gas is given off, nor copper precipitated on 
it from a aolution of that metal when touched by 
zinc. Gas cnke, however, recently ignited, or 
plumbago, plaofd uoder similar circumstances, 
copiously evolves hydrogen from its surface. The 
same circumstance is noticed with the Tarioua forms 
of porous coke and boxwood charcoal, but in theso 
cases no gas is given off for some little time. Ob* 
serving this, it is a matter of great interest to know 
wh^ became of the gas for the first few seconds, 
and it directly occurred that the first portions of 
gas were bound down in a nascent state with the 
charcoal : this was proved by placing it in a solu- 
tion of copper, when the charcoal and the coke 
became coated with a thin film of the metal. In 
the same way gold, silver, mercury, and lead, vren> 
precipitated from their solotions, and iocfine set free 
from iodic acid. Probably the other metals were 
also precipitated, but their colors render a thin film 
dlificiilt to be distinguished. lAHien charrosJ or the 
porooB coke is made to form the electrodes of a 
battery, the piece forming the kathode or platinode 
is fbmd to have similar properties ; but the anode 
or nnoode, however, is ftraad to 



190 



MAGAZINE OF SCIENCE. 



ozfgeo from iU libfratiiig chlorine from mttriatic 
acid, thongb this is not quite so satiftfactory ai the 
experiment with the hydrogen. The gu coke aad 
ptiimbsgo Hre found not to posaeu the property of 
retaiDing the gase«. Occaoonalty diarcoal wiU bo 
found to precipitate gold and Kilver from their so- 
lutions, but in theae caaea copper, and those metala 
which have a greater affinity for oxygen, ftr« not 
reduced. 

" View the importance of theM eiperiments, aa 
they demonstratively prore that which has hitherto 
been tlie prevailing theory, namely, that nascent 
hydrogen precipitates the metals, and that the pre- 
cipitation may takn platre when the galvanic current 
ii broken ; for the coke will retain ita hydrogen in 
aome cases fer forty-eight or more hours. Now in 
what state is the hydrogen when it ha^ tliese pro- 

Sertiea ? Is it in the form of minute bubbles aii- 
ering to the surface ? This would appear to be a 
mj-stery. It is probably in a state analogous to so- 
lution ; for if a piece of smooth plntinum be placed 
in contact with zinc till minute bubbles are covering 
ita whole surhrc, and then the zinc be removed 
and a solution of a metal be poured npon the pla- 
tinum in such a way that the bubbles are not dia- 
torbed, no prcdpiution takes place ; and even 
spongy platinum or spongy palladium fails under 
the Kame ciministancea to precipitate the metal. 

" Much diRiculty arises in naming the two poles 
of a battery ; they are c-allcd the positive end and tlie 
negative end, the anode and the katliode, the pla. 
tinode and zinrode ; now as each pole of a simple 
battery becomejt reversed if the battery is dunb]ed, 
it is better to name the two etida ^m the oxygen 
and hydrogen ; since we have shown that the gal- 
Tinic current owes ita power of decomponng many 
substances entirely to these gaaei. The nones 
which are proposed are ozode, at which oxygen is 
evolved, and hydrogode, where the hydrogen is 
given off. 

" The soft and spongy charcoals, as those of deal, 
possess the property of evolving gas very imperfectly. 
" Various kinds of coal, snrh as anthracite and 
cannel, were tried, but none were found to evolve 
hydrogen, nor to have copper precipitated when the 
drcait was made in a solution of that metal. 

" From tlie a'wve experiments we see that bsttc- 
ries may be constructed of carbon in the place of a 
negative metal ; the hard coke or plumbago aa- 
awering htAt, and the porous coke and box-wood 
charcoal next. Tliese mny be used as an ordinary 
battery with sulphuric acid, but of course a battery 
tboB constructed possesses but little power. If, 
however, the liydrogen is removed upon Professor 
Danicll's principle, then will the power be increased, 
and a charcoal battery may be made of tnirprising 
energy. The hydrogen may be removed by me- 
tallic solnttons, which have n feeble affinity for 
oiygeUf and therefore those of gold, silver, plati- 
num, or copper, would answer best ; the latter 
being the only one in use from its cheapness. The 
highly oxygenated acids, such as nitric, itc, ere 
more powerful Chan these, and are now considerably 
employed ; but disadvantages attend their action, 
for if the current is required to be continued for a 
long time, a large quantity of acid must be used* 
and the fumea arising from the battery are injurioua 
to tbe animal economy : in addition, the strong add 
is liable to be spilt over the fingers or clothes ; and, 
lutly, it always transudes through the porous tubes, 
and acts upon tlie sine, even when amalgamated, to 
a considerable extent. 



" It ia perhaps worthyof notioe, that tbe 
of tbe nitric add battery are not to be attribnteJto 
the fluids alone, for no current is formed whm 
platinum is use